List Item revision mismatch

The actual revision of the List Item does not match the expected revision.

• Your update to this Sync List Item has conflicted with a request submitted elsewhere.
• The value specified in the If-Match header is erroneous.

If your update conflicts with a concurrent update elsewhere, the correct solution is to read the latest data (on the client SDK: wait for an update) and then re-attempt your update until you succeed. Consider that, since the data has changed, you may not want to submit the exact same update a second time. On the JavaScript SDK, we suggest using the mutate convenience function.

The value you provide in the If-Match header should be a revision assigned by the Sync service when interacting with the object.

• In SDKs, this is the revision field, part of the object descriptor.
• When using REST (e.g. via the Twilio Helper libraries) this is the ETag header provided in responses.