You can first check to see if you have power from the fuse and also at the window switch.
You can also jump out the connector terminal switch to the other side of the connector terminal switch and see if the window goes down
Being sitting that long and not being operated can develop oxidation on the power switch.
You can use electrical contact spray can at the window switch.
If you do have power going to the window switch and it still won't go down then replace the window switch