1) Make sure the price submitted in the feed, matches the price on the landing page and structured data.
1a) the landing page should only show 1 price, if you have other prices, make sure it is read after the initial price. For example if you have RRP, then have the RRP on the right hand side of the normal price. Also make sure the font is equal or greater then any other price listed
1b) make sure the structured data shows the correct price, if you have variants listed, make sure the variant selected is the first element within the structure data.
2) if the manufacturer has submitted bar codes, they you need to add this too. If the products don't have bar codes, then clear the fields mpn, gtin and brand and set identifier exists to the value no
you can use feed rules for this. More info: https://support.google.com/merchants/answer/7450276?hl=en-GB