I have twice recently been refused applications to open savings accounts.
The reason - the road I live on does not have a name, and the on-line application forms insisted on one. I live on a country B-road in Monmouthshire, away from any village, so I put the B-road number. But this B-road number is not a normal part of my address, which I give (if I am allowed to) as ", near , Monmouthshire, ". My applications were rejected because the address did not match word-for-word with that on the utility bills etc which I was then asked to produce.
One application was for a Post Office Savings acccount - you would think they of all people would understand address problems. I stood for 5 minutes in my local Post Office listening to the clerk having an argument with his head office over this (and losing).
I said I am in Monmouthshire, and that is another problem. During (I think it was) 1974-1995 this area was in the county of Gwent. Many on-line forms ask for the house number/name and postcode, and then Boom! they expand this into a full address that they get from some database. Very clever, but more often than not they give my county as Gwent. But Gwent no longer exists. Moreover, the Welsh Assembly, in its wisdom, are talking about changing county boundaries yet again. So my various utility bills and bank statements have various addresses for the same house and there is nothing I can do about it.
One building society branch manager advised me "Don't apply for accounts on-line, it can be a can of worms. Apply in branch if possible." So much for "Joined-up Britain".