I’am using the **smpplib **library to send SMS from python code, the **register_delivery **flag is set to True in my submit SM request and the **DLR **is well received in the Deliver SM.
Below isthe message received in the Deliver SM :

Nid:00003f25a4 submit date:2405031740 done date:2405031740 stat:DELIVRD err:000

The message id is the same as received in the SUBMIT SM RESP. Despite this, my service returns a status “Invalid System ID (0x0000000f)” to the SMSC.
I tried to figure out where the status 0x0000000f is generated in the smpplib codes (link below) :

https://github.com/python-smpplib/python-smpplib/blob/master/smpplib

i didn’t find any explanation. Has anyone faced this case? How can I resolve this and send status **ESME_ROK ** instead?