Important:
This answer is based on tax law for the tax year ending 28 February 2020.
Answer:
Unfortunately, the letter that you refer to was not attached to the request. It may have been that the system didn’t allow for it to be added to your request. In order for us to comment on this we need to know what the grounds for the disallowance of the deduction is. The will appear from the IT34 or the letter that you refer to. Please advise what the exact wording of the letter is, or the grounds that were provided on the additional assessment.
It was common for SARS to disallow the deduction where these receipts didn’t contain all the information that was required by section 18A(2).
As there is an additional assessment it may well be better to request reasons for the assessment.