My mom is a permanent resident she spent most of her time
in Panama. Last time she came immigration told her the she have to
come to U.S. every 6 month. Not every year like before.
Please if some body have any info. On this matter please.......
Thank you.....

Let me try to enlighten you a little bit about the residence subject. The purpose of being a "permanent resident in the U.S." is that you actually live in the U.S. Being a permanent resident of one country but living in another does mean in the U.S. that you will loose your resident status. Other questions to consider are: Does she pay taxes in the U.S.? Does she have any ties to the U.S.? If your mum wants to continue to be a U.S. resident, then I can only recommend to spend more time in the U.S. or give up the residency.