UC housing element and non-dependents

Current situation
Mother (56) renting from local housing association. Claiming UC and Carers Allowance
Lives with two non-dependents - her adult children, let’s call them A+B (27 & 31)
A+B are unwell (same illness, different stages)
A is claiming PIP (special rules) and ESA
B is claiming PIP (not special rules) and UC
Neither A or B are able to claim housing costs because they are living with a relative.
However, both are in receipt of low income.

Mother’s housing element has been deducted £171.46 for ‘2 adults living with you…’
My understanding was that if a non-dependent is in receipt of PIP then the housing element is not calculated in the same way.
Can someone confirm?
Many thanks

Paragraph 16(2)(e) of Schedule 4 to the UC Regs covers this: no housing costs contribution for any non-dep who gets the daily living component of PIP.

thank you for confirming

I suspect the root of this is how these non-dep were reported on UC as I’m pretty sure you report that non-deps get PIP directly in the claim. Not sure if it’s possible if the PIP award came after the UC claim and it’s not been updated?