Error: 'The transaction is either not associated with the current connection or has been completed'

After deleting a task, I cannot save the plan due to the following error message:-
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​An unexpected error occurred. Please report this problem to your system administrator with the following information:
System.InvalidOperationException: The transaction is either not associated with the current connection or has been completed.

The functionality has been enhanced in Orchestrate version 7.76 hotfix 30 and Orchestrate version 7.77. Please upgrade to either of these versions or above.
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If the issue continues to occur, please raise a new case online and reference the title of this article.