Safari autofill passwords

Why am I having trouble / difficulty saving passwords for autofill to keychain in iOS? Using iOS 15.2.1 on 5th gen iPad and am an experienced iOS user. I’m not in Safari “Private Mode”. Settings>Passwords>Autofill Passwords is ON. Settings>Safari>Autofill>Name and Credit Cards are ON (no “password” option here). Registered on a site, choose “use strong password” when prompted. No other prompts. Went to site login, tapped on “username” field. No prompt except “Passwords” at top of on-screen keyboard. Pressed that and Password App/keychain shows no record of site or username (manually and using search). Back to site. Reset password using same process as above. This time after choosing “Use Strong Password”, there is prompt to “Save Password” which I do. Log out. I check Password App - no saved password or username for site. But when I try to login again, the Blue Button appears asking to use username and then the fields autofill (though again, no data in the Password App when I checked beforehand). Able to login as it should work. Log out. Try to login again. No Blue Button prompt. Check Passwords app and still no option for this site. Reset password, this time using my own password. After waiting 10-15 seconds, prompt appears to “save password”, which I do. Log in and out several times without problem. Now, finally, the site, username and password can be found in the Passwords App.

Why is this process so glitchy?