Q: reason why your body is not holding protein

A: Not sure what you mean by this exactly, but in general our bodies will always excrete some protein as waste (dissolved in urine). The exact amount of protein your body can make use of and whether the protein will be burned for energy or used to repair muscles or tissues depends on a lot of factors, so there is no one answer. But to put it simply, if you eat more protein than your body can make use of then it will discard some or all of it as waste.