Inspect the kickstand for metal damage and make sure it can move between the up to the down positions. If it can't, replace the entire kickstand assembly.
Move the kickstand to the down position and lubricate the metal beneath the moving lever with WD-40.
Tighten the pivot pin bolt of the kickstand. Make sure it does not rotate abnormally.
Turn the bicycle upside down. Tighten the kickstand plate bolt with your wrench. Make sure this assembly does not rotate or move horizontally.