This happens even after I recently upgraded my Virgin SIM-only deal to a Samsung Galaxy J3 (2016) deal, thinking it was down to the software being out of date for 4G on my old phone.
I have a sneaky feeling this only happens in one particular location and is a fault with the network/cell-site I connect to when I'm at home as I've had no reports of people getting the engaged tone when I'm in the office.
Customer support are unable to help - I've contacted them several times over the last 6 months without getting a successful resolution. I think it requires someone with more technical knowledge and I'm hoping such a person will read this posting and assist me with the issue.
Hi Richard, There are others but they don't really use their phones for calls that often. I'm pretty sure it's happened on a Windows 10 phone, a while ago though. I will try the 3rd approach, but I think EE are possibly not aware of the problem with the cell site, which is why it hasn't been fixed. Regards, nahunt27