This version of Nextcloud is not compatible with PHP 7.2

Hello,

I upgrade nextcloud 13 to 14 and finaly to 15.
I get an error message first :

Some columns in the database are missing a conversion to big int so I run this command to fix it

sudo -u www-data php occ db:convert-filecache-bigint

And the last error is

This version of Nextcloud is not compatible with PHP 7.2.<br/>You are currently running 7.2.15-0ubuntu0.18.04.1.

Nextcloud 15 is compatible with php7.2 so maybe ther is a bad entries somewhere ?

Could you please help me ?

It should be compatible. For some reason, the update did perhaps not finish correctly and parts are still on the older version. Can you check the version in your config/config.php and in versions.php?