sorry, it is not possible to combine collection from two different accounts.
If you have forgotten or lost your other account info, please write to customer service.
the need for 2 accounts should not be required.
Some of the Members who do Beta testing, have an account for that purpose.
but other than that, all cards should be purchased on one account only,
unless you really do want Some cards on one, and some cards on another.
but they can not be combined into one.