Remove the door panel: Locate and remove the screws that secure the inner door panel to the outer door panel. Once you've removed the screws, carefully separate the two panels.
Realign the gasket or seal: Check the gasket or seal to see if it's damaged in any way. If it is, you may need to replace it. If it's not damaged, gently realign it with the groove on the door where it is meant to fit.
Reattach the gasket or seal: Once the gasket or seal is aligned, press it firmly into the groove around the door. Make sure that it is securely in place and not loose on either side.
Reassemble the door: Once the gasket or seal is properly in place, reattach the inner door panel to the outer door panel using the screws that you removed earlier