We’ve white listed that IP for you again. Unfortunately last time we continued to receive a high number of irregular calls. Hopefully that should now work fine!
I’m afraid we’ve had to reapply the block. The issue is still not resolved, I think we received around 1,000 invalid calls in the last 24 hrs. These are repetitive calls with the invoice ID set to -1, the account in question only has a few invoices so the volume is way out. Can you please ask your developer to look into this, thanks.