How to handle an expense receipt with wrong vat amount calculated on it ?

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I'm just doing some expenses and one item has a printed receipt stating that the VAT rate is 20% however the total doesn't match.

Total: £541.50
VAT @ 20% £108.30
It would appear they've just divided the total by 5 and used that for VAT.
The VAT should be £90.25.

How should I enter this as an expense for accounting purposes ? Do I use the correct value or the one printed on the receipt ?

Thanks,
Tony.