Nomination + back button(Android,2.99)

As mentioned before,faced and reproduced a bug. While submitting poi,press "existing photo" (works with current photo and nearby),then app opens gallery(in my case "Simple Gallery pro" bought not cracked,i just dont like google photo) AND - then "back" button does nothing(meant to step back to photo options(retake/use gallery etc) (down left button,i can't use gestures 'cos of third-party launcher doesnt support them on my device,stock only,so i use two-button navigation) so to choose "take photo" i used to restart app and resubmit. BTW it behaves the same with inbuilt google photo
App is 2.99.1 from store,phone is Motorola One Power on latest stock available Android one(10)(actually it's chinese 6/64 Lenovo P30 note but afaik it's fully the same as OnePower but with 6 ram).
Comments
Sorry about grammar:) Actually i remember some builds ago back button worked normally in this use-case.Maybe smth changed because i've reflashed stock,idk. If any additional info(eg adb logcat) is needed please inform.