I would like to share this, because solving this problem took me some months...
My Sasmung Galaxy s23 was using two physical sim cards. I also have a Galaxy watch 6 classic LTE, and I planned to add a e-SIM to my smartwatch.
I installed the e-sim onm my phone, transferred it to my smartwatch. And turned the e-SIM off on my phone and eventually I deleted the e-SIM completely from my phone.
Looking back: this caused the problem: I was sometimes unable to make a call or receive a call with SIM1. Symptom: when I made a call, the phone is making a call, but I could not hear the tone what is is calling. When the other side picks up the phone, the connection was broken. Incoming call sometimes got through and sometimes I only received the sms-code reminding me of a new voicemail.
I searched for an answer:
* Switching the SIM-cars between slots: the problem still occurred (with the same SIM-card)
* Maybe a broken SIM-card, so I ordered an replacement: the problem still occurred.
* I searched for answers, reset the SIM-settings etcetera: the problem still occured.
Eventually I made a hard reset, and the problem was solved.
So, I presume, somehow the old e-SIM settings were still somewhere on causing problems on my phone, causing this problem. What I don't understand is that only the same SIM card always has the problem -> because I also switched SIM-card between the SIM-slots. Besides that it would be handy if there is somewhere documentation: adding a e-SIM to your smartwatch when already making use of two physical SIM-card in a phone.
Anyway: it works eventually. I hope I helped someone.
