IMS call dropped (SIP cause undefined)

Hi All.

What may be the reason of these call drops?

Where is this packet captured?

At eNodeB or UE?

Captured at UE.

Is this flow of L3 messages same for all drops?

In this specific case, PTI is not being recognised at network end, and eps bearer context requests are dropped.

It may be due to mismatch in PDN related settings at network end.

Involve Core end engineer to jointly investigate through traces.

Yes, This is the L3 Flow and Same for All drops.

This is dedicated bearer request.

As per trace it shows normal deactivation.

Can you get this? Check if it’s coming from Core?

Same error I’m also getting.

Don’t know why UE sending PDU session release request…