Hi,
that log message could happen for tons of reasons and it's really not
saying much alone.
I don't think GPRS is needed at all or has any relation with USSD.
Please provide a full pcap file with gsmtap and logs of the full run,
otherwise it's almost impossible to guess what the problem may be.
--
- Pau Espin Pedrol <pespin(a)sysmocom.de>
http://www.sysmocom.de/
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