I have a BT phone which has BT blocker. It has been workingvfor months no problem. Now when i try to make a call using the handset it says UNABLE TO MAKE CALL AS DEALING WITH AN INCOMING CALL or something similar. If soneone calls my numver then it just rings. The ipenreach engineet is stumped as line chevk all ok and using his equipment he can call in & out it seems to be my handset. I have gone into the call blocking settings and it wobt gice me the option to switch off.