Maybe it needn't be said, but really consider migrating whatever site requires it from PHP 5.6 to at least something more current like 7.4 or best is to move to the 8.x code branch. I had one hold out customer still running an ancient Joomla install that still required PHP 5.6. Nag, nag, nag them to upgrade to WordPress! (Their site was as out of date at the underlying code, so a complete refresh was in order anyway!)