It finally came. Check your Tello account.
How rude of them
You would see this message if you were on a monthly plan, and changed to PayGo.
I don't know if that is what you are seeing.
I see that (and never had a plan) but the paygo balance is still there further down.
Mine seems to be working fine.
I thought Tello said they would notify customers before accounts were canceled.
Tello:
"Even with Halloween season coming up, we’re not planning to trick customers into anything or close our doors to people who have been using this product. We will come up with new features in the near future, and in the meantime, no Tello number is expired without prior notification by email - don’t believe anything else you hear. The changes were supposed to clarify some of the questions from customers."
https://www.nthcircle.com/forum/tello/2859-tello-minimum-payg-20?start=60
For lines still have Tello Dollars, you can purchase new plan ($5 minimum) with Tello Dollars. For lines only have little PAYG balance, clarification from Tello will be needed if those numbers can be ported out without buying a new plan.
OK, if I look at my Tello dashboard on a line with a monthly plan, there are 2 blocks/frames of information.
The top block is my monthly 'plan', and shows bargraphs for remaining data, text (and presumably minutes if my plan included that), with a box to the right showing "My Plan" information.
The bottom block is for my PayGo balance. (I have some Paygo balance for minutes.).
By happenstance, I switched back today from straight PayGO to a monthly plan-- but before I switched back, I saw the same box on the right hand side saying Your Plan Has Been Cancelled: Buy New Plan, where my dashboard currently gives "My Plan".
On a straight PayGo account (never had a monthly 'Plan'), the top block has only the box on the right hand side with the Your Plan Has Been Cancelled: Buy New Plan text: the lower block shows my PayGo balance and info as it should.
Remember that in Tello terms, 'cancelling a plan' is not the same as 'cancelling an account'. 'Plan' refers to a recurring monthly charge.
I think we're just seeing an artifact of the new dashboard layout.
On the other hand, I still expect to see account cancellations very soon, unless Tello decides to let them unofficially slide by for the time being.
I'm disappointed that Tello has not done anything that I can see to reach out to customers.
They definitely can be ported out if they're ported out before the line/account is cancelled. If the account is cancelled without a few days notice, and the number is important, I'd talk to them immediately to insist, and file an FCC complaint right away if that didn't work.
Speaking of porting, the new dashboard still does not show account number, but it does have a menu item to access your account number. Select My Phone from the menu, scroll down to Port Out Information, and enter the Account Security Pin that Tello emailed to all of us a few months ago. The account # appears immediately. Probably a good idea to grab that account number now if you don't already have it. (The email had the subject line "Your Tello Security Pin is here.")
Has Tello changed PaYG terms? I see this message on dashboard, "You can use Pay As You Go balance for international calls & texts." So if you're on $5 plan (data only), you can't use PayG for calls in U.S? Only international calls & texts? Confusing.
You can still use Tello PAYG for domestic calls/texts.
I see this as a marketing decision to encourage customers to sign up for a monthly plan, since PAYG credit now expires without a plan or PAYG purchase before expiration.
"Pay As You Go is prepaid credit for your national and international calls, texts and data at affordable rates." International Calling with Tello Mobile
"What can you do with: $20
United States 2000 min/$20
SMS 2000 texts/$20
Data 1 GB/$20"
I haven't gotten anything from Tello but over the last three months I've swapped phones several times (just to check whether the phone was truly Sprint network compatible). Those are technically "Orders" at $0. I hope they consider those orders sufficient to keep the line active without any paying activity.
I recently switched to the $5 data plan but turned that data off and I'm using my Paygo balance to make and receive calls in the USA unless something has changed in the past few days. I would guess the "you can...international calls and texts" message is intended for people on paid plans who have unlimited US t&t and who wonder what Paygo is for. But, yes, rather vague wording.
I didn't any notification on my account with Paygo.
And I have no order in the past three months.
Really not sure...
Hello guys,
Thanks so much for reaching out! God, you're fast 
We're sorry, but if you got this particular message, please know that it was due to a bug. Rest assured, it is now fixed. Please check your account again, and if anything should look a bit off, we encourage you to contact our Customer Support Team so we can get it sorted out.
We stand by our word, no expiration will take place without prior notification, no need to worry about that.
Thanks again,
Your Tello Team
That Pay As You Go rate page has always been confusing. For some reason, it defaults to rates for Columbia. You have to select United States to see domestic rates.
I think you have a very optimistic outlook..
This would be an interesting loophole.
I believe the voicemail is also reset when swapping device.
I noticed the same message in my accounts. I have a Tello flip phone in each of my cars as an emergency phone. I decided to switch to Free Up and use their free plans with the only requirement being to login to the accounts and click off that I want to continue with the free plan each month. I've been requesting my pay as you go balances back from Tello. So far so good. If you request a refund, please include your paypal account email.
It's a shame to see Tello go away for Pay as You go service. I must say for the many MVNO's that I've used, Tello has always been a 5 star provider.
How do you swap phones at Tello? Do you need the IMEIs? Anything else?
Technically, the MEID (instead of IMEI), and the ICCID (assuming that the device uses a SIM card.)
It's a good idea to check the MEID before getting started on the Bring Your Phone tab, to make sure it's eligible.
(Some older devices may no longer be compatible with Sprint auto-provisioning. It might still be possible to activate some of these for voice & text only, but not data, through some manual programming steps.}
The swap can be done in your online dashboard. Select My Phone and then (under Want To Replace Your Phone?), select Bring A New Phone.
The swap should complete almost immediately. You'll need to restart the new phone. If it's been used on a carrier before, you might need to 'kickstart' the process by a dialer code if it doesn't go into hands-free activation on it's own.