Approval transaction errored out by the system

Summary:

We saw a case where an approval transaction was errored out by the system but do not understand why it happened.

Content (please ensure you mask any confidential information):

Below is the approval flow - the transaction was assigned to a role that a few users have, one of them claimed this transaction and requested further information from the initiator. The initiator did not reply and 3 days later, the transaction was released back to the approver who had asked for the further information. When the approver tried to request information again - at that point the system errored out of the transaction. I know the system releases transactions that have been claimed but not acted upon after 3 days but in this case, there was a pending information