Guy I used to date randomly contacted me, not sure how to proceed

We dated for maybe 3 months a year and a half ago (Spring 2024) and ended on mutual terms due to circumstances out of our control (not to call it a “right person wrong time” ordeal but in a way it was)

Out of the blue last weekend he texts and says he’s been thinking about me and wanted to check in. We somehow fall into casual conversation and he drops that he’ll be working in my area soon.

How do I ask him, in a not so blunt way, why he decided to contact me other than his initial text reason???