Hello Amr El,
Is there some custom code or logic implemented to your solution ? For example, there will some more specific Storage Location determination based on the values maintained in the custom Tables containing the Sales Area ?
If that is not the case, we need to check the Bdocs for the error messages. And then probably, we can block the queues and can ask a technical consultant to debug the validation modules.
Hope this helps.
Thanks,
Samantak.