App for repeat/persistent notifications? (Moto G4 Play)

I have a Moto G4 Play that I spent a few days trying to convince myself to carry daily.

My problem: I haven't been able to find a setting that allows persistent audible notifications for incoming text/missed calls. (And I think I've read in the Moto forums that it's not available.....)
I work sometimes in noisy environments, and depend on persistent notifications to catch my attention when I move into a quieter area. Without it, I'll swap back to my old phone.
I've seen a few apps in the Play store, but wondered if anyone had experience with any?