Try wiping your pits with white vinegar. It kills off the bacteria so kills off the smell. You do smell a bit vinegary at first but it soon fades.

With the tops try spraying them with white vinegar too and leaving to soak for a bit. Then throw them in a hot (as hot as machine and clothes allow) wash and it should help.
If the sweat is old stains you may have to do this a few times, or they may past it. But give it a go

HTH