There are occasionally order that fail or delay sync into OMS from Marketplaces, to fix this, you may use the "Sync Order" function. Should the order is not processed from MP or cancelled, the order will be able to fetch into OMS after.

To find : Integration -> e-commerce -> Marketplace, click on vertical dot to find the manual sync button.

Shall the issue still persist, kindly disconnect & reconnect the marketplace stores and try "Sync order" once.

Should above 2 option are not able to solve the issue, kindly reach out to our customer support team help@selluseller.com and our team will assist to check and fix accordingly.