After removing mail account, the corresponding data of the account such as contacts, calendars etc. still persist in Horde database. If the mailbox with the same name is recreated, this old data (except messages) will be available to the mail account.
The issue occurs in case the webmail role was assigned to a stanalone webmail node or another service node.
The behavior was considered as internal software issue #PPA-2806.
The fix is considered to be included in one of the next PA updates.
Please use provided ID to track maintenance in Plesk Automation release notes.
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