CIS tax return for deceased - lack of information

My boyfriend passed away in October 24. We did not live together however have a son together. Although self employed, he was a joiner and worked in the CIS construction scheme, paying 20% tax at source. As his estate was very small, under £5000 and we are in Scotland, there is no executor. He did not leave a will. I informed HMRC of his death using Tell us Once. He would have paid too much tax as he only worked for part of the year and was ill for a number of months. I do not have access to all of his online accounts/ payslips to obtain info to complete a tax return. What should I do in this situation?

Hi amalit,
We will need to access the record to review this for you.
Please contact HMRC here:
Self Assessment: general enquiries
Thank you.