### Describe your issue Can not place phone call. Can not receive phone call. Mobile data and SMS service is mostly working. (Mobile data stops working when the phone becomes hot, but it can be easily worked around by removing rear phone cover.) #### Expected Behavior Can place and receive phone calls. #### Observed Behavior When I try to call to PinePhone from different phone. 1. First call after power up when the phone is not sleeping yet. PinePhone rings shortly and call is imediatelly disconnected. 2. Second call to PinePhone in a row: Line is busy When I try to call from PinePhone to some other number, call immediately ends. I don't know, how to obtain some logs. As if I open gnome-calls from terminal the command immediately ends with no output and then Calls application opens. #### Specific area or package affected Is reproducible with vanilla mobian-installer-pinephone-phosh-20220731.img.gz image installed. The problem don't disappear when the updates are installed. ### How reproducible is the bug? Always. ### What device are you using? PinePhone ### Which mobian repository are you using? File /etc/apt/sources.list.d/extrepo_mobian.sources doesn't exist. Content of mobian.list: deb http://repo.mobian.org/ bookworm main non-free ### How did you get your Mobian Image? * https://images.mobian-project.org/pinephone/installer/weekly/mobian-installer-pinephone-phosh-20220731.img.gz ### Solutions you have tried I have tried different SIM card from different operator and it didn't help. But phone calls used to work on Mobian with some previous release. The hardware might not be the exactly same as working one with some older Mobian release. It is my first try to use the phone after its mainboard was replaced by PINE64 due to its RAM died.