mozillla or thunderbird is changing an email password blocking my access

mozillla or thunderbird is changing an email password blocking my access to send email from account it will not accept the password i set for account, in saved passwords it has a huge password stored that i did not set ,,also that password is not accepted it was hard enough to get that email set up on a w10 pc and a w11 laptop, this problem started when i allowed an update to t-bird, further updates have not helped on update 115.10.1, it want to update again, i have use mozilla and t-bird for 30+ yrs and the problems keep getting worse not better and has become almost user unfriendly. to add an email, should require 1)user name,, 2) email address, 3)password. thats it , it shouldnt require a IT degree to set up the rest