hello!
M66_Series_AT_Commands_Manual says that CCID
may contain non-digits:
Example
AT+CCID // Query CCID of the SIM card
+CCID: “898600220909A0206023”
OK
It is a real example? As far I know, ICCID should be treated as decimal number.
Same ICCID used in +QCCID example.