Topchook has the better take on this. It sounds to me that things have changed and she no longer wants to stay. Otherwise why wouldn’t she require cleaning as the remedy? Or, yes, have requested it prior to signing.
Her choice if she leaves but she is still liable under the fixed term you have both agreed to.
I would offer to visit to take note of her concerns with a view to remedying. I suspect she will refuse this because it won’t suit her true agenda.
If she wants out, she needs to request early release. Once new occupants are in, you can refund her for days unused at that point.
Document ALL exchanges via email. If you receive a text or a phone call, respond civilly as usual but email soon after documenting your incoming call and what was said/agreed/disputed between you. Don’t initiate casual communication yourself, however wherever possible.
As always, imagine all is to be potentially read by a third party such as legal council either for or against you.
It seems you are being bullied (by your account.)
Take free professional advice rather than just from a forum which is heavy on landlords but short on qualified advisers. I would respectfully suggest National Landlords Association or, if not a member (you should be!) Openrent. Citizens Advice also has contacts if they can’t or won’t help directly.
Always make as sure as you can that you are talking to someone who really is well placed to know the facts. Forums encourage well meaning wishful ‘I thinkers’ & bloody-minded, gung-ho types on occasion, along with the rather well informed. Spot the difference if you can.
Stay strong. Stay professional. Be guided by your own Agreement and your conscience. If the place needs a clean, clean it.
Member NLA (accred)
I am not a professional adviser; I just don’t get out much.