I'm scared of the phone

For as long as I can remember I've been scared to answer the phone, if I don't know the number I literally can't pick it up and I can't phone people either. I feel like my SO is fed up of it, if I ever need to phone the bank or anyone he'll offer to do it on my behalf but other times he'll say "why didn't you answer it" and I just say I couldn't and he's like "well you should have anyway@ yesterday I got a phone call that I didn't answer and they left a voicemail saying it was about a job I applied for and when I told him he asked if I answered it and I said "no I couldn't but even if I did I wouldn't be able to hear her because you were playing a game" and he just said "you should have just phone her"