Can't add or edit product from backoffice prestashop 1.7.3.3

[maryam]

server setup and configuration

Apache Version 2.4.34
PHP Version 7.0.30
MySQL Version 10.2.16-MariaDB
Architecture x86_64
Operating system linux
Max execution time: 30
Upload Max File size: 1024M

Memory limit: 1030M

• PrestaShop version (source) : 1.7.3.3
• debug mode report : i'm using debug mode but it shows no error message 
• PHP error logs : at first it showed a symphony error long short description, now it shows no error 
• apache error log : no error 
• javascript console log : no error 

I installed prestashop 1.7.3.3 and i'm using the classic default theme but i can not add or edit any product. But I can access/edit the other stuffs in the catalog. when i am trying to edit/add getting a msg 'unable to update setting' and the it spin for a long time. 

i looked from errors it gave at first the error that the short description is too long i changes the max size of the short description to 8000000 it's changed in DB too but same problem, i tried to comment the short description size checking but now it says that the product is saved but when i reload the page the inserted data disapear.

Does anyone know how to fixe this issue ? thnx

[musicmaster]

Changing the size of short_description is a bit tricky as it may be handled on different places in the code. 

Try to get things working first in a default setting. And only then experiment with these kind of changes.