Suddenly cannot log in admin module

Everything was functionning well for the last couple of year, and suddenly to day, when trying to log in my admin module, I have this error message:

Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 4864 bytes) in /home/partage/public_html/Wordpress/wp-includes/registration.php on line 213

I have not woorked on it recently and everything was alright the last time.
The blog itself is alright: https://taraquebec.org/Wordpress/

Any ideas ?

Martin