I think it’s the other way round. Mass warps space-time which creates gravity.
Quote “Einstein eventually identified the property of spacetime which is responsible for gravity as its curvature. Space and time in Einstein’s universe are no longer flat (as implicitly assumed by Newton) but can pushed and pulled, stretched and warped by matter. Gravity feels strongest where spacetime is most curved, and it vanishes where spacetime is flat. This is the core of Einstein’s theory of general relativity, which is often summed up in words as follows: “matter tells spacetime how to curve, and curved spacetime tells matter how to move”.
This is what seems to be what happens but why it happens see @Mariah‘s answer above.