eNodeB high drop connection due to RRM UE S-TMSI duplicate

Dear Experts.

eNodeB is having high drop connection due to RRM UE TMSI duplicate. Can anyone elaborate what is this issue.

Dear @gdtelecomm ,
Have you solved this issue?

Then, could you share what cause the S-TMSI duplicate?
I have the same issue now.

I don’t know why the UE transmits connection request while it is already connected at a eNodeB side.

The risk of duplication occurs when an allocating MME node restarts.

In order to avoid double allocation of TMSIs after a restart of an allocating node, some part of the TMSI may be related to the time when it was allocated or contain a bit field which is changed when the allocating node has recovered from the restart.

In areas where both MSC-based services and SGSN-based services are provided, some discrimination is needed between the allocation of TMSIs for MSC-based services and the allocation of TMSIs for SGSN-based services. The
discrimination shall be done on the 2 most significant bits, with values 00, 01, and 10 being used by the VLR, and 11 being used by the SGSN.

Every MSC is configured with its one or more specific NRI (O&M). One of these specific NRIs is part of every temporary identity (TMSI) which the MSC assigns to an MS. The TMSI allocation mechanism in the MSC generates
TMSIs which contain one of the specific NRIs in the relevant bit positions. An NRI has a flexible length between 10 and 0 bits (0 bits means the NRI is not used and the feature is not applied). The use of the bits not used to encode the
NRI is implementation dependent (e.g. to extent the TMSI space). An MSC applying ‘Intra Domain Connection of RAN nodes to multiple CN nodes’ shall allocate TMSIs to the served MSs.