Landlord trying to retract a promotion at the end of tenancy.

I signed a 12 month tenancy with a 6 month break clause on the basis that my offer, made in writing to the agent, was conditional on one month’s free rent. The offer was accepted, the free month was applied at the start of the tenancy without any conditions attached, and I made all subsequent payments on time. Eight months in, I exercised the break clause and submitted notice. The landlord is now demanding repayment of the free month, claiming it was only valid if I completed the full 12 months. This condition was never mentioned at the offer stage, during referencing, at contract signing, or anywhere in the tenancy agreement itself.

The landlord’s argument is that the Entire Agreement clause means pre-contract representations are irrelevant. My understanding is that this does not extinguish a misrepresentation claim under the Misrepresentation Act 1967, and I also think there is a logical issue with claiming I had to complete 12 months when the contract itself contains a 6 month break. Has anyone dealt with a similar situation, and would the Property Redress Scheme be the right route here, or is small claims more appropriate given the sum involved is around £1,075?