Incorrectly placed on Simple Assessment

Hi, I have Lasting Power of Attorney for my mother's financial affairs and submitted her Self Assessment in May this year. I have just received a letter from HMRC placing her on Simple Assessment. However, the Simple Assessment is incorrect because it misses out her foreign income - she receives a foreign pension. The same thing happened last year, I rang HMRC who placed her back on Self Assessment. But the Self Assessment helpdesk is currently closed until September - what should I do?

Hi Dominic Kini,
If you click on 'Ask HMRC online' and state 'speak with an adviser' when the bot asks for the reason for contact, you will be put into a queue for webchat and we can review this.
Self Assessment: general enquiries
Thank you.