Beware - there is lots of dodgy stuff out there. Are you based at a university in Manchester? I'd suggest wondering around a few buildings (especially the humanities, social sciences and education ones) and taking details from those posters people put up in corridors offering proofreading and editing help. That way you are likely to find someone who is based in Manchester, and though it isn't what they'd normally do, one of them may be willing to offer some actual help and advice about writing (rather than just returning a proofread and edited document to you) for an extra cost. I think they're less likely to be dodgy than a lot of online stuff. The one above seems like it could be legit (it is hard to tell), but the other day on the radio there was a whole program about these sites that actually do the work for you (the substantive part of your work - i.e., cheating), which clearly isn't what you want.
This one is definitely legit, as I used to work for them (so I know it was purely editing not questionable services): https://www.bioedit.com/ But I don't think they offer actual teaching sessions - they will just edit the manuscript and give extensive and helpful comments to do with clarity, grammar, structure, and style.
Other than that, have you tried academic writing classes? Could be helpful if you are at a uni that offers them.