Different Loan Type
Each type of federal student loan has a different limit. If you reach the limit on one type, you still might be able to borrow using one of the other types. For example, if you are at the limit for Perkins loans, you can switch to Stafford loans. If you have reached the limit for subsidized Stafford loans, you can still get unsubsidized Stafford loans, as long as you have not reached that limit. If you are in graduate school, you can get PLUS loans, which have no limit.
Private Student Loans
Private lenders do not set specific dollar limits on how much you can borrow per year. However, they do approve loans on an individual basis. If you cannot get approved on your own because you have debt that is dragging down your credit score, you might be able to have someone with excellent credit co-sign with you to get approved for another loan. You can usually borrow up to the cost of attendance for each school year.
If you cannot borrow from any other source, you will need to pay your school bills with your own funds or money from family members and friends who are willing to contribute to your education. If you don't have enough money saved, you could take fewer classes per semester. That way, you can work more hours and earn enough to keep up with your expenses while you finish your degree.
If you are studying at a university with a high tuition costs, and you've reached your loan limits, you might want to consider transferring to a different school to finish your degree. Choose a school with a low tuition cost per credit to limit your expenses. You can also try to find a school near a relative who will let you live rent-free while you commute to school to save even more money.