Hi there!
Thank you for reaching out.
The order number sequence is typically stored in the EasyStore database tables. Since you've restored an older backup, the sequence has likely reverted to the value that existed at the time of that backup.
The sequence can be reset for invoice ID, but there is no option for order ID unfortunately. Here is a screenshot of the relevant options in EasyStore general settings:
https://cleanshot.com/share/01cvV6Tm
Reference: https://www.joomshaper.com/documentation/easystore/general#order-id
Hence you need to edit the order table ID from your database directly to get the desired order number as follows:
https://cleanshot.com/share/6dDwYH8w
Best regards,
Rashida