Hi @DM ,
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Routine monitoring can refer to this Microsoft document:
According to your description, there seems to be a data conflict. Please see this document: Peer-to-Peer - Conflict Detection in Peer-to-Peer Replication.
There are some Conflict scenarios in the last part of this article.
Peer-to-peer transactional replication lets you insert, update, or delete data at any node in a topology and have data changes propagated to the other nodes. Because you can change data at any node, data changes at different nodes could conflict with each other. If a row is modified at more than one node, it can cause a conflict or even a lost update when the row is propagated to other nodes.
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