I've noticed that you're working on multiple message tracking reports at the same time, which can cause long delays.
When the report is ready, you will be notified of the reserved recipients.
You can consider temporing your query or simplifying your search criteria.
In addition, you can use the command to terminate the query.
Stop-HistoricalSearch -Identity <SearchIdentity>
More information can be found Message trace in the new EAC in Exchange Online | Microsoft Learn
Stop-HistoricalSearch (ExchangePowerShell) | Microsoft Learn
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