@Peter_Litchfield
By turning on User Debug in Config->Logging I trapped api response showing PHP error
Looks like running out of memory available to PHP:
Fatal error</b>: Allowed memory size of 536870912 bytes exhausted (tried to allocate 268435488 bytes)
I’ll need to check code to see if I’m batching because look like you have 165 fax events.
You may need to increase your memory_limit in php.ini