2.2.1 Upgrade Error Cannot Upgrade Cs-Cart Please Read

I have hired CS-Cart Rocks to do an upgrade to 2.2.1 but he is getting the following issue:

“Could you submit a ticket to cs-cart that the upgrade will hang at “dispatch=upgrade_center.check” and finally got a 500 Internal Server Error.

I've checked the folder permissions and it seems no problem. Let's see how cs-cart respond.”

CS-Cart I have opened a ticket with you and have support points can you please resolve ASAP? I provided the ftp login in the ticket. Noone has responded.

Ticket # is: ID: #100364240

Can you please fix? Why is this happening to me?