YMB, I would complain to the Branch Manager and to Customer Services as that is not acceptable. In the meantime, could you or your daughter not print off an A5 or A6 sheet explaining your daughter's deafness and asking the other person to remove the face covering to enable lip reading as the Regulations permit?
You might want to make it a wee bit snapper and then laminate it or take a photo and save it to the 'phone.
Action on Hearing Loss (the trading name of the RNID) has a sheet that can be downloades.
It wouldn't be clear to me I was being asked to remove my face covering and I fed that back to them a while ago.
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