Apple ID/Account email won’t change

Hi,

I’ve tried to change the email account on my Apple ID several times but it won’t change.

I used to have an Apple ID in the email I’m trying to change to, but deleted this account a while ago now but it still won’t let me change the email address.

Any ideas? I just keep getting error messages and then sometimes saying the email is in use. When I then try to do forgot password on that email it says the email isn’t registered or something to that effect.

I never use the email associated with my Apple account now but have had it forever so unwilling to set up a new account!