Hello,
For the product page the same template applied on all the single product pages which you have chosen from Theme Settings >> Product Page >> Product page design. Only the inner content changes according to products but the layouts still remain the same.
In your case if you face different page templates on different product pages then edit your those products and go to “PRODUCT DESIGN & COLOR OPTIONS” from the “Product page design” select “Inherit” and update the product.
Screenshot for clarification: https://jmp.sh/Keoo0L6
Best Regards.