Hi, I had the same problem.
Sometimes this error may occur when you create product and price condition with different log on language.
In my case:
1) I log on with RU language and create product. Then log off from the SAP.
2) I log on with EN language and try to enter price condition, but get error "Sales organization *** does not exist".
3) I log on with RU language and sucsessfully create price condition.
I hope it may help.