Protons are said to be massless, but a proton may have mass that is so small that we cannot measure it easily. We can't currently say with 100% certainty that it is massless- only that it is at most very, very small: < 1×10−18 eV/c2
Because if so, and assuming you have some reason for believing this i.e. you can prove it, I would urge you to forward these findings to a physics journal of your choice posthaste, as this basically represents a total refutation of much of physics of the last century or so. You will easily win a Nobel Prize.