Upgrade 22.04 to 24.04 PHP 8.1 to PHP 8.3 on Apache2

I seem to have a similar problem, my apache2 has stopped working, I believe following an upgrade to 24.04.
systemctl status apache2.service includes this error message -

apache2: Syntax error on line 146 of /etc/apache2/apache2.conf: Syntax error on line 3 of /etc/apache2/mods-enabled/php8.1.load: Cannot load /usr/lib/apache2/modules/libphp8.1.so into server: /usr/lib/apache2/modules/libphp8.1.so: cannot open shared object file: No such file or directory

It is correct that /usr/lib/apache2/modules/libphp8.1.so has gone and been replaced with /usr/lib/apache2/modules/libphp8.3.so

What do I need to do to get it to work again?
Thanks
Mick