Changing A Phone/broadband Provider

[Questman]

I run a small business from my home. I moved to a new address about three years ago and set up a phone line and broadband in the name of my business with a small provider. Being a business line I was able to choose a memorable telephone number which I am very attached to. I contracted for a two year period and after two years I advised my provider that I had not been happy with his service for a number of reasons to do with billing errors and poor speed of fibre broadband and that I would not be renewing the contract with him. Since then the service improved and so I continued with him but without making a new contract.
Last month I had no broadband for 14 days due I think to a problem between my provider and his supplier.
After putting up with daily promises that my service would be up and running the next day I advised my provider that I was giving him notice and would be moving to another business broadband supplier.
My prospective supplier has advised my current provider three times that they will be porting my number and migrating my service to themselves but it seems that without giving any reason my current provider is able to stop/prevent me leaving him.
Does any member understand the law relating to these matter or have any suggestions on how I can get to change provider?

[Zacs-Master]

Some advice here under 'Problem changing broadband provider'
https://www.ofcom.org.uk/phones-telecoms-and-internet/how-to-report-a-complaint/changing-provider

[Buenchico]

The information under 'Problem changing broadband provider ' on the Ofcom website might be relevant to you:
https://www.ofcom.org.uk/phones-telecoms-and-internet/how-to-report-a-complaint/changing-provider

[Buenchico]

Snap!

[Questman]

Thanks both Zacsmaster and Buenchico.
I know of Ofcam of course but you made it easy by sending me the link.
I've now submitted my complaint. I'll advise when aanything changes.