RM530N-GL: QMAP Mode Ignores AT+C5GNSSAI - Multi-Slice Not Working

alan1321 · February 4, 2026, 5:00am

Hi,

I’m trying to establish multiple PDU sessions on different network slices with the RM530N-GL.

What works: Multi-PDN on the same slice (using QMAP + quectel-CM)

What fails: Binding each PDU to a different S-NSSAI → Error 265 (ROUTING_FAIL)

Root cause (confirmed via PCAP): In QMAP mode, the modem sends only SST:01 in the Registration Request, ignoring AT+C5GNSSAI configuration. The AMF only allows SST:1, so
any CGDCONT profile with a different S-NSSAI fails internally.

In non-QMAP mode, the modem correctly includes all configured slices - but then we lose multi-PDN.

Question: Is there a way to get QMAP mode to respect AT+C5GNSSAI and include multiple S-NSSAIs in the Registration Request? Or bind different PDU sessions to different slices?

Firmware: RM530NGLAAR05A01M4G

Thanks!

silvia · February 13, 2026, 8:54am

Dear @alan1321
Do you network support multi S_NSSAI?
The Allowed-NSSAI can be reported by URC +C5GREG and queried by AT+C5GREG? or AT+C5GNSSAIRDP. If the network allocate multiple NSSAIs, the result should be separated by “:”.E.g. +C5GREG: 1,“1”,“290D4025”,11,4,“01.020206:02.010103”.