From the details provided, I understand the search feature may not work due to the modification of the Pipedrive API.
As stated during the during our call, Pipedrive is a third party application which is integrated with flow.
You mentioned that you have reported the issue to the Pipedrive team and is being currently worked on.
I would suggest you follow up with Pipedrive services and also the Pipedrive community as further action to resolve this may depend on them.
On the call, I asked for your consent to temporarily archive the case pending the time the issue is fixed by the Pipedrive team and if you have issues with the flow, you can re-open the ticket and we will be glad assist.