It's a bit unfortunate HMRC don't publish more accessible guidance on this. But the post by "HMRC Admin 20 Response" (24/11/2023 8:47 AM) is accurate if not particularly illuminating.
I hope the following is helpful to others but please let me stress that it does not constitute advice and I am no tax professional.
HMRC currently (Jan 2025) provides no routine mechanism for allowing individuals to indicate that a UK bank account held under their own name (possibly jointly with another person) is actually operated for the benefit of separate entity (e.g. an Estate or a beneficiary of a Trust). Therefore HMRC will attribute interest earned on money held in such an account ("savings income", a category of personal income) to the named account holder(s).
If it's a joint account, HMRC will assume the interest is attributed 50% to each of the two joint account holders.
See also
https://www.gov.uk/apply-tax-free-interest-on-savings
To resolve this income being misattributed, soon after the end of the applicable tax year I wrote to HMRC at -currently- their "Pay As You Earn and Self Assessment" address, see
http://www.gov.uk/government/organisations/hm-revenue-customs/contact/income-tax-enquiries-for-individuals-pensioners-and-employees
In my letter, I identified myself (name, address, National Insurance number, tax reference numbers) and the relevant bank accounts (bank/building society, sort code, account number, account holder name(s). For each account I indicated the value of the savings interest and how it should be attributed (e.g. the Estate's details, inc. tax reference number, or other beneficiaries details (inc. name, address, and national insurance number if known). Unfortunately, my letter was not properly assigned within HMRC and -unfortunately- ended up with the inheritance tax group. So it may be wise to phone HMRC around 6 to 8 weeks after you post the letter to ensure it reaches the correct destination its contents are understood correctly. At the end of the executry period, don't forget to pay the tax due by the Estate on any savings income, if such tax is due.