If you look at particle accelerators, the anti-matter storage is still very much experimental with anti-hydrogen storage holding it for less than 20s at most.

If you look at particle accelerators, the anti-matter storage is still very much experimental with anti-hydrogen storage holding it for less than 20s at most. We can trap individual particles (e.g. protons) for a long time but things get exponentially more complicated as you increase the size of the system. Hell, we can't even store hydrogen without leakage issues and with anti-hydrogen any leakage is very bad.