Hi there @Tjbosworth
What type of phone are you using, corded or cordless? Can you see what socket you have?
Does it look like this? With the bottom half having a line accross it?
If it does do you feel able to carefully remove the bottom portion? Be careful for wires. Once removed plug a Corded phone (if possible) in and try calling your number. What happens?
Excellent. Glad it sorted the issue.