Expired tenancy

My tenancy expired 3 months ago, I decided to leave the property and gave my landlord 4 weeks notice, under my old tenancy agreement I would have had to give 2 months notice, the landlord is insisting that I have to still have to pay the rent for 2 months as I did not give 2 months notice and is expecting me to pay the rent for 2 months even though I have left the property, can you kindly enlighten me what the situation is as my agreement expires in November the estate agents informed me that I can not sign a renewal agreement as my guarantor was not willing to sign the renewal agreement

Shelter (https://england.shelter.org.uk/housing_advice/private_renting/ending_a_periodic_tenancy) and the citizen’s advice bureau (https://england.shelter.org.uk/housing_advice/private_renting/ending_a_periodic_tenancy) are good sources of reliable information.

I believe, assuming you pay rent weekly, that 4 weeks notice is sufficient. If you pay rent monthly, it should be one month after your next rent payment date (so, depending on dates anywhere between 4-8 weeks).