Valve cover oil leak

Oil is leaking from my valve covers around the bolts. The gaskets are new and the bolts are snug, but not super tight. Oil is leaking from the center bolt on the bottom side of both of the valve covers and drips onto the manifolds. What to do?
I would remove the valve covers and check to see if the mounting surface is warped by previously over-tightening the valve cover bolts.

Put a straight edge on the mounting surface around the holes to see if the surface is warped. If so , lightly tap back into shape so they are level again and remount , don't forget to check if the washers are in place. Use new gaskets and snug up bolts to about 9 ft/lbs in crisscross pattern.