Historically, banks sat outside the reporting arrangements that other lenders worked within. There was no obligation on them to tell Experian, Equifax and TransUnion anything about your current account.
That's been changing. More banks now share data, because it improves their own decisions as well as everyone else's. But it remains voluntary, and some still don't participate. If your current account is missing, that's the most likely reason.
You can ask your bank to start reporting your payment history to the agencies. Whether they do is entirely up to them.
Why the balance shows as £0#
Where an account appears but the balance reads £0, it's because no borrowing is in place.
Balances show where credit is actually being used — an overdraft you're into, a card with a balance on it, or an energy account in arrears. An account in credit has nothing to report as owed, so £0 is correct rather than a gap in the data.
Why savings accounts never appear#
Savings have no bearing on credit reporting.
Your credit report records borrowing and how you handle it. Money you've put aside isn't borrowing, so it has no relevance to creditworthiness as the agencies measure it. However much you've saved, it won't appear on your report and won't feed into your score.
That surprises people, and it's worth being clear about: lenders assessing affordability may well ask about savings during an application. That's a separate assessment from anything on your credit report.