Woocommerce sorting is not working with mdtf plugin

Hello,
I am working on the woocommerce site and i need to sort the products using the custom fields. I am also the using the mdtf plugin for filtering the product. The sorting is working fine for the first time but when i choose the filter options from the mdtf plugin then the sorting is not working. Please help me through this. I have to use this plugin , its compulsory.