Problem to delete contact(s)

Problem to delete contact(s)

Hi ! I noticed today that I could not delete contacts in my Zoho Invoice. Every time I have a error message in French as you can see on my screenshot:


Google Trad: ""Customer Order Disabled Enable sales orders to access customer order settings."

I can not delete one or more contacts at all. I searched everywhere to activate this famous "Customer Order". The most amazing thing is that I have two organizations with a standard plan. Each under a different user and with different parameters. And I have the same problem on both.

Would that be a problem at Zoho or have I missed something?

Any help will be really appreciated :)