Why PHP script (ecommerce) has been rejected? Please help

Hello.

Several times I sent my job and received the same answer: “We have completed our review of <seller - Universal E-Commerce Marketplace> and unfortunately we found it isn’t at the quality standard required to move forward, and you won’t be able to re-submit this item again.”

My script:
Frontend:
http://shop.creativecode.site

Backend:
http://backend.shop.creativecode.site
login: demo@example.com
password: 112233

Advance Thanks & Regards,
Vladimir