Business Registration Number Invalid

Trying to get my seller account reverified, though one of the last things I need to do is to add my Business Registration Number so I can go get my account verified, but no matter how many times I try to add it, I keep getting the same response.... INVALID NUMBER! I have absolutely ZERO idea as to why Amazon is telling me this, I'm copying and pasting it in directly from our business registration documents, as well as copying it from the government Companies House website, so there should be no rejection!

Anyone else get around this? If so.... how? What do they actually want?? I'm racking my brain as to what Amazon wants, I just want to get back to selling again! Why does Amazon make things so pointlessly difficult just to do a simple task??