I actually just answered this on another post, but you seem to already be port forwarding.
The following ports would need to be changed (4 in total):
- InBound–> ALLOW TCP @ P:30110-P:30120
- InBound → ALLOW UDP @ P:30110-P:30120
- OutBound–> ALLOW TCP @ P:30110-P:30120
- OutBound → ALLOW UDP @ P:30110-P:30120
Out of curiosity, what’s your hosting provider? Seems like a inappropriate way to handle customer service. Either way, the question applies because, sometimes, they have strange external firewalls on their management panels.