Call forwarding has come on my phone i didn't activate it now it wont let me deactivate

[Lisa712]

I was expecting a call earlier, the caller then text to say they couldn't reach me. I was asked to call them, when I did this an ikon with conditional call forwarding came on. I haven't put this on but when I went to deactivate it keeps telling me I need to there is no network and no sim. I have checked the network, it is fine. I have also switched phone off then back on still nothing.

[caesarome]

Call Sky on 150 and report this issue to them.

[Rooo1]

I also noticed this began on april 13th and it is still saying conditional call forwarding active when i call out.

I don't know what to do as when i try to change it it tells me i can't 

[Rooo1]

My VOLte symbol has also disappeared so only 3g calling is available and not 4g like usual. I can only think that it has something to do with the outage.