It is difficult to understand your question, therefore impossible to answer. It also appears that you may not understand what you were told, or that you are not reporting it accurately. It is not at all true that your payment cannot exceed 31% of your gross income - many borrowers' payments exceed 31% of their gross income. It is a goal of the HAMP program, where the rest of the parameters of the situation fit the HAMP formula, to REDUCE the housing cost to 31% of gross income.
No one can provide meaningful help without a detailed interview with you and an analysis of all the details that would relate to an attempt at modification. You should retain the services of a knowledgeable financial services attorney.
Please note that the above is not intended as legal advice, it is for educational purposes only. No attorney-client relationship is created or is intended to be created hereby. You should contact a local attorney to discuss and to obtain legal advice.