SA200 -v- online tax return

My husband, up until last year received an SA200 to fill in and send off. Some years ago we were in an IVA and he was given a temporary UTR and did his accounts online (I never understood that). However, some years ago he reverted back to his usual UTR. Unfortunately now he is unable to do his accounts on line, because his old UTR is still in the system. We have written to HMRC twice (no reply), tried to call (hours waiting on line), no helpline available. WHY???

Hi
As he was in an IVA, the original UTR should not be used.
He should contact us on webchat to have this updated - Go to Gov.uk and search 'contact HMRC'.
Then choose Self-Assessment and go to 'Ask HMRC Online'.
Thankyou.

We tried using your "Ask HMRC Online" system for the above to happen, and we cannot get any sense out of it. We need to speak to a human being.