You need to be more specific. What store? What item?
Some stores, like Walmart, Target and Walgreens, have receipts that contain numbers that tell Ibotta what you purchased. Other stores don't and you must scan the barcodes for the items,
Double check that you bought the correct products at the right store. Most rebates are not available at all stores. You can pull up the details on the rebate and scan the UPC. If the UPC doesn't match, then you may have the wrong variety or flavor.
If you still think you bought the correct item(s), you will have to submit a request. Be sure to include a copy of your receipt, a picture of each item AND the UPC of each item that you did not get credit for. It can take up to a week to get a response.
Sometimes, new UPCs are added and Ibotta may not have them in their system yet.