There is many info about using Caller ID feature, setting up and testing if it can work with your modem on this tutorial. Also it shows you how to test the modem output and check it is giving the results you expect before implementing with SambaPOS
I suggest you read through it and spend some time testing directly with Putty as suggested in the tutorial to verify it works.
If you need personal help via Teamviewer, this could be available but would be a paid support service. You may post a topic in the Ads category for paid support. You may also send a PM (private message) to me if you like, our company provides paid professional support for SambaPOS.