Password lost i can't confirm my phone too

I lost all data on my phone then i download the app from apk file and i can’t verify my phone because i used then and i don’t remember my name or my password what i can do

You can just register again from scratch, just enter same name and number and choose “I lost my account” when asked. It will overwrite your account with a new one. You’ll have a new key and all buddy relationships will be lost of course.