One of our flows started failing recently. We identified the sign-in log entry, where the following info is available:

According to our current understanding, here's what happened:
- An external built the flow on a VDE / VM,
- by using a service account,
- a long time ago (months back),
- the connection was automatically refreshed successfully for all this time (months), since there was no password expiration
- the VDE / VM was disabled in our AD tenant on 31.01.2024
- the flow started failing
The flow fails in the Send an HTTP request to SharePoint action.
We checked the connection and it seems valid (there's no warning / fix the connection message).
If there's a possibility that the flows will start failing every time a device used to BUILD the flow is disabled, then I am really concerned about using flows for any solutions I develop from now on. The exception handling, maintenance and monitoring measures to prevent failures become ridiculous.