XBee S6B DNS lookup unsuccessful

Hi, I’m stability test a unit using TinyGSM code and I’m periodically not getting a DNS lookup even though the network appears to be good.

I’ve seen an unrecoverable error twice.

The first time it had been running for at least 3 days. The 2nd time it had been running 50hrs.

The TinyGSM code’s algorithm is to wait with retrys for at least 45seconds for an ATLA IP response.
For unsuccessful ERROR responses it waits 100mS and then retrys.
I’ve seen it retry over 200times with the 100mS wait between each retry, so the WiFi network appears to be good.
When I reset the main processor, which does a reinitialization of the XBEE (not hard reset) it then sucessfully completes ATLA.

Any suggestions as to error recovery.