The six beliefs that cost money here
Each of these is a reasonable assumption and an expensive one. None is a claim about intent - every one is a statement about a mechanism that can be checked in the terms that contain it.
"One account each means one account per household"
The obligation is written per person, not per address. Two adults in one house each hold their own account lawfully, and the comparison is designed with that case in mind: a shared address, network and device are ambiguous signals that do not decide a pair on their own. What the household genuinely shares is the risk of a review, not a breach.
"A shared address is enough to link two accounts"
An address alone is not. It is free to compare and weak on its own, which is why ambiguity has its own band. What changes an outcome is a payment instrument in one name funding two accounts - mid-strength on its own and decisive in combination, because it also engages the requirement that deposits come from the holder's own funds.
"A second account is always deliberate"
Forgotten logins, changed email addresses, name changes and duplicated registrations all produce duplicates, and they are ordinary administrative problems. The comparison cannot tell them from a deliberate second account, because the signals are identical - which is why raising an accidental duplicate before it is found is the one input a reader controls.
"A finding means the deposits are kept"
The clause that permits a retention exists, and the ordinary resolution is narrower than a reader fears: deposits into the unrecognised account are normally returned, and what is removed is the growth and any bonus built on play the operator declines to recognise. On the arithmetic used here, growth and bonus were about 71% of the balance and the deposits were returned.
"Removing the overlap fixes the review"
Changing the card, the telephone number or the address once a review is open does not remove the overlap the review is about - the comparison already holds both records. A pattern of changes during a review is recorded, and the evidence that actually moves a case is a separating document rather than a corrected field.
"A second account at another operator breaks the same rule"
It does not. The singularity obligation is per operator, so one person with accounts at five operators holds five lawful relationships, and the comparison that matters is never run across two companies. The same holder is in breach only by opening twice with one of them - accounts per operator, never accounts in total.
What the six have in common
Every one of them comes from the same place: a reader reads about their account, and the rule is written about a person. An account is a screen with a balance on it; the clause is a description of a relationship between an operator and a legal individual, enforced by comparing identifiers neither side of the conversation can see. In that sense this desk is not really about duplicate accounts at all - it is about the difference between the thing a product gives a reader to look at and the thing the terms define.
Read the two that apply to you
A reader with a partner, a flatmate or an adult child on the same address should read the shared household and then the signals. A reader whose account has already been held should read the consequences first and the appeal second, in that order, because the arithmetic and the evidence window are different questions. The remaining pages - the comparison, the rule and the second account - are the reference material behind both.