You should make sure that you put all requests in writing. I wouldn’t do it by email or text but do it by post. Tell the agent that you are requesting this information under section 48 of the Landlord and Tenant Act 1987 and that under the act, you are entitled to withhold rent until such time as the addresses provided.
Also tell them that under section 1 of the Landlord and Tenant Act 1985, if they don’t provide this information within 21 days they commit a criminal offence You would need to take those proceedings in the magistrates court because the police will not be interested in
It doesn’t matter why you want to know the address.
Here it is from one website in more detail.
You would need to take those proceedings in the magistrates court because the police will not be interested
You could also get the title deeds to the property from the land registry for a fee of £3 but be aware that many landlords simply put the address down on the land registry deeds as the address of the property which does not help you. Here is the link to the land registry website.
Can I clarify anything for you?