English Language requirement for naturalisation

[unfair]

My sister submitted a B1 certificate for her ILR and her application was granted. She has submitted the same certificate for her naturalisation application and has received the below:
It is noted that you have provided a Trinity certificate dated 10 April 2017 as evidence that you have met the KOLL requirement. Please be advised that as this qualification has not been accepted previously as part of another application an has expired (2 year validity), this document cannot be accepted. Please now submit an alternative certificate which meets the requirements explained on the attached annex.
I think the caseworker has made an error due to the below which is on the gov.uk website:

Applying for citizenship
You can use a B1 level qualification that’s run out if you’re applying for citizenship and it was accepted when you settled in the UK.
It does not matter if the B1 level test you took is not on the current list of recognised tests. You do not need to take another test.

We intend on replying, quoting the above. What are your thoughts?

[contorted_svy]

Did she tick the box that this certification had been used for ILR? Make sure to clarify that.

It may be the quickest to go ahead and book a SELT English test and send that if the back and forth goes on for too long.