求翻译：你好！由于我们的店铺是属于个人经营的，所以无法给你邀请函，必须是公司发出的邀请函才有效，这个之前已经试过了。是什么意思？

How do you do! Because we belong to the individual business practices of shops, so can't give you an invitation must be issued invitations are valid, this had been tried before.