Shopify Product IDs changing (Google Ads)

Our Shopify product ID changed after adding variants to products. The old IDs started with shopify_US, and the new ones are strings of 13 numbers. Our Google Ads campaigns relied on the old IDs to identify products. After removing the variants, they didn’t revert back to the original IDs, but back to shopify_US format. Now, our history with these products is lost, and we’ll have to rebuild our campaigns. How can we fix this and restore the original product IDs?