UPGRADE DOLIBARR TO 10

I tried to upgrade my old dolibarr to version 10.0.0.
I follow the steps on page “http://myip/dolibarr/htdocs/install/check.php?testget=ok” one by one and after the last step “upgrade from 9.0.0 to 10.0.0” and the page “http://myip/dolibarr/htdocs/install/upgrade2.php?&versionfrom=9.0.0&versionto=10.0.0” I received error 504, UNDEFINED.
I restarted dolibarr and I received again the page:
http://myip/dolibarr/htdocs/install/check.php?testget=ok
I repeated many times the last step “upgrade from 9.0.0 to 10.0.0” but i have the same resaults.
Any help pls?