Landlord asking us to pay a share towards a professional clean !

Hello, I moved into this property in Lewisham just over a year ago. My friends were already living here (they moved in 2-3 years before).

We are all currently in the process of moving out. The landlord sends us WhatsApp message saying:

The property will need a professional clean. The house needs to be in a similar condition to when you moved in, as it had a professional clean before your tenancy began.

There was no professional clean before I moved in. So I’m a bit confused where I stand.

Thank you for reading!!