MAP invoke inside a TC_cont not recognised as such

MAP message (ISD) is too long for one MTP frame, so it is segmented at MAP level into multiple TC messages WS successfully recognises the first, inside TC_begin, both in - Packet List Frame - with protocol as GSM MAP and name of operation in info column - Dacket Setails - with correct analysis of structure But the MAP invoke inside the tc_cont is not recognised (it's valid - I analyzed the BER by hand!!!) Am I doing something wrong?

Thanks Steve