wordpress multiple meta value query is not working

You use the “p”-argument, which looks for the wordpress Post-ID. I guess you want to search the products, that have $product_id in the meta, not for the exact post with the ID $product_id. Just remove the “p” argument from your wp_query arguments.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)