Hi @nurdiyanamusa ,
Thanks for your message, and welcome to the community forum. You should only receive timestamp errors for DOIs that have previously been registered.
The error message ‘Record not processed because submitted version: ___ is less or equal to previously submitted version (DOI match)’ indicates that the timestamp in your deposit is numerically lower than the timestamp used in a previous deposit.
Every deposit has a value (called the timestamp), and that value needs to be incremented each time the DOI is updated. The timestamp errors do indicate that the DOI has been deposited, so if the metadata and URLs previously deposited for the DOIs are correct no further action is needed. You can find the most recent timestamp by reviewing your past deposit XML. Timestamps are also listed in the depositor reports available here: crossref.org : : depositor
@eatoni, on our support team, wrote a community forum post about this in 2022. You can read it in its entirety here: Ticket of the month - August 2022 - Solving that timestamp error!
If you still believe you have DOIs that are not being registered, can you provide me with those DOIs so I may take a closer look?
Warm regards,
Isaac