Error: The sort failed because there are no more unique mailpiece sequence numbers for your Mailer ID.
Please select a later mailing date or obtain another Mailer ID
The USPS requires that sequence numbers remain unique for 45 days. When the Sequence mail pieces parameter is set to Automatic, the Bulk Mailer system keeps track of the date and the sequence numbers used. The program also looks for a continuous sequential block of numbers large enough for all the records that are being sorted; if it does not find a large enough block of sequential numbers available, it will produce this error.
Note: Bulk Mailer does not allow sequence numbers to be reused for 90 days.
1 . Obtain another Mailer ID to use until the current Mailer IDs sequence numbers are released for re-use. Once a second mailer ID is obtained through the Business Customer Gateway, create a second permit by making a copy of the current one, and use the new Mailer ID in that one.
2. Sometimes restarting the whole server could do the trick
How to request an additional Mailer ID