Lost password username

simple thing probably for everyone else but I have been using the same program for around 4 months and now I am logged out and require the user name and password I have tried everything and reset does not allow for some reason. Any ideas for a desperate person who knows very little I might add.

Can you try the occ user:resetpassword command? On Ubuntu:
sudo -u www-data php /var/www/nextcloud/occ user:resetpassword admin_account_name