By that point money ceases to have value, because the value of money comes from the motivation it gives people to work. If AI does everything, then money is useless (unless AI like money for some reason).
There will still be a need to distribute and exchange ressources, goods and services.
Real estate, food, energy, mobility.
That will be done with money. Or violence. Either way, a scary future to people when labor doesn't provide any value. Elon promises abundance, but what can he do against greed?
there are always be next frontier of problems which require creativity, unless AI become supersmart completely make humans redundant in all cognitive functions.