Start with the moment discharge changed. Valve movement, feeder response and the level trend together show whether attention belongs at the outlet, in connected equipment or higher in the stored mass.
Read the last normal discharge and the first abnormal response as one sequence. A falling level with no material at the feeder points somewhere different from an unchanged level above a running discharge line. This sequence explains why silo material stops flowing and which part of the system belongs in the next review.
Keep any recent product change, moisture event or maintenance on the discharge equipment beside that sequence. One of those changes may explain the first abnormal response without requiring operators to test the stored load from below.
Compare material bridging with rat-holing and poor flow, then send the safe observations with your cleaning enquiry.