We have sat her down twice. The first time after the cell phone incident. I explained that she needs do differentiate a work phone from a personal phone. It's a common mistake even in the west with work phones and laptops so I have her the benefit of doubt and blamed myself for not giving clearer parameters.
As i said, salary advances are also common. We have it because we don't want to have them with no money but explained that we won't be doing it again next pay day and they must learn to live within their means.
I also had a counseling session over the change. I explained how every peso must be accounted for. That normally we would leave them with petty cash but can't do it if they take advances or can't account for the money we give them.