What would you check first if consumers are reading the same messages multiple times after a deployment?

Checklist: 1) Was the consumer group ID changed? (new group ID means new consumer group starting from auto.offset.reset). 2) Were offsets reset manually during deployment? 3) Check if commits are happening before vs after processing. 4) Was the topic recreated? (new topic = no committed offsets). 5) Check enable.auto.commit setting — if disabled and manual commit has a bug. 6) Verify __consumer_offsets topic is healthy — describe the consumer group to see committed offsets. 7) Check for broker-side duplicate replays from log corruption (rare). Most common cause: group ID change or offset reset during a deployment script.

Expected key concepts: group ID changed, offsets reset, auto.offset.reset, commits, enable.auto.commit, manual commit, topic recreated, __consumer_offsets, deployment script, duplicate replay, group ID