Teams tags is mainly focused on the general issue of Microsoft Teams troubleshooting. Since your question is related to approvals, which is not in our support scope. The following idea is just for your reference.
Is it possible to use Approvals in Teams to approve PIM Activation requests?
Yes, it is possible to use Approvals in Teams to approve PIM Activation requests. You can create an approval flow in Power Automate that triggers when a new PIM Activation request is submitted, and then use the Approvals action in Power Automate to create an approval request in Teams. When the request is approved or rejected, the flow can update the PIM Activation request accordingly.
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