I'm a newbie on 3CX and needs help to solve this issue: Calling from YEAlink phone to any extension is possible any time. Calling from softphone (pc or iphone) to YEAlink phone is possible only after I soft reboot the YEAlink phone. But after a few minutes I cannot call anymore the YEAlink phone from my softphone. My softphone (pc or iphone) displays only service unavailable. Thanks for your help.