I know it can be confusing when something like this occurs. In this unusual circumstance, it appears that a change to the institution might have caused Mint to no longer recognize the account, and created new ones in their stead. It is rare, but it does happen from time to time. Generally, however, the duplicated accounts will not go away on their own. There's a couple of things you can do to resolve this.
For any duplicate transactions you find, if the accounts were added recently, or you're not concerned with being able to immediately view the transaction history for the older version of the accounts, go to the Accounts menu at the top of the page in Mint, then click the Hide tab, and change the status of the older accounts to Hide from Everything.
Otherwise, if you don't want to hide that data, but you have duplicate transactions, you will need to go to the Transactions page and mark transactions as duplicates. Check the boxes for the affected transactions (if any) and then click Edit Multiple at the top of the transaction list, then mark them as duplicates so that they don't negatively impact your Mint profile.
You will need to mark the old accounts as Closed, to make sure your net worth is being displayed correctly on your profile. To do this, in the Accounts menu, find the account in question on the Financial tab and change its status to Closed. This will not make its balance apply to your Mint profile, but will not remove any historical data.
Let us know if you need any further clarification or assistance. Because of the complexity of this issue, if you prefer more direct assistance, please Contact Mint technical support or use our chat option from the Support page (appears during business hours only, 5-5 Pacific Mon-Fri) so our support team can further assist you.
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