Commercial property service charge dispute - locked out

[judas]

Just heard from a friend that he turned up at his workshop this morning to find the landlord has changed the locks. He's been in a dispute with them for quite a while over the service charge - basically they aren't maintaining the place properly and are refusing the provide a breakdown of the charges. He's withheld payment until the agreed amenities are restored and cost breakdown is provided. However, his rent has always been paid on time.

So to the questions:

1. Is the landlord permitted to do this given that the rent is up to date?
2. If not, is he allowed to force entry?

He's operating a one-man business so the impact is massive.

Edit: this article implies that the landlord has acted illegally: https://www.anthonygold.co.uk/latest/blog/forfeiti...

article said:

Forfeiture by peaceable re-entry is not available for any other breach other than non-payment of rent. For any other breach of covenant, a landlord must serve an s146 notice pursuant to the Law and Property Act 1925.

Edited by judas on Tuesday 18th July 12:28