On this page https://staging.die-edelhelfer.de/ortlieb-back-roller-classic-ql2-1-fahrradtasche-paar-aphalt-black.... when I click on add to cart the product is not added. Instead the page is reloaded and I see the error message: Unique constraint violation found
When I look in the browser inspector in the response there is nothing.
Normally there should be  for Json response I think.
Could someone please help me with this problem?
Hello @Nevaf Ay,
It can be possible due to your DB is not being properly imported. There is some broken reference in that.
So kindly check that again.
I hope this will help you to resolve your issue.
If not, feel free to contact us.
If worked? Click KUDOS and accept as a solution.
Thank you @namitapare2a78 for the answer.
The return is "All modules are up to date."
The return is "Nothing to import."
After that I can add one Simple Product to cart.
But it works only one time.
When I try it ones more with another simple product the error is the same: Unique constraint violation found
What else can I do?