Why does Medicaid say my Mother can't have taxes taken out of her school retirement?

My Mother is a retired school teacher living in nursing home with alzheimer's. Medicaid told me she can't have taxes taken out of her monthly retirement but Mothers tax preparer says if she doesn't have them taken out she will owe around $1100 at the end of the year. So, she doesn't have enough to pay the nursing home, her supplemental insurance and Medicare. I have been to 3 attorneys for advice, talked to Social Services at the nursing home, called Medicaid several times, went to our local Medicaid office and I still don't know what to do. Can you please help me? My husband and I are on Social Security and we have to put money in Mothers account every month so her bills can be paid. Thank you!