Ring pro 2 transformer

I just installed a pro 2 doorbell, it is working fine. Doesnt ring my existing chime, but just discovered mine isnt compatable (will just get a ring chime, no biggie). However, when checking device health it shows in red 15v, poor voltage. Power level 1. Do I need to swap the transformer if its preforming ok? And if I do, how do I know which one to swap ( we have front and rear doorbells-ring only on front. So there a 2 transformers on breaker box labeled chime)? 1 reads Chime 16v, and the other Chime 5VA 10 V. I can only attach 1 pic. Thanks!