Passwords in iPhone disappeared

My iPhone password keeper has disappeared after latest updates. What do I do? Thank God I have a different password manager but I had my iPhone long before a different manager but I still use the iPhone manager. I cannot now because it is gone! Normally when a password is needed I am asked which password manager to use. Now, my phone only can find my password manager and not the original one with iPhone. I will be afraid to ever again run an update.