Trouble in logging to the new instance

Hi All,
For a new company yesterday I had registered a single user instance, there was no issue in setting it up, later I was I tried logging out and then logging, at this junction it was not allowing me to log in, then I requested for password reset, after resting I was able to again login, now changed the password logout and then tried to login again, not possible, again tried to change the password, not possible , now no away to login back.

I hope this is the correct forum group to post
Have any one faced such issue, is there any issue like this noticed
Joseph John

Can you share the screenshot of errors? What you get when to try to login or reset the password.