If the automatic setting on your dryer doesn't seem to get your clothes as dry as it did when new it could have a malfunction or more likely the two electrodes that act as moisture sensors and control the automatic cycle may have a film of dryer sheet residue covering the electrodes and signalling that your clothes are dry before they actually are.

Reddit user spasticpoodle suggests periodically scrubbing the electrodes with steel wool, a Scotch Brite pad, or emery paper and that you should do this every time you clean the dryer ducts and scrub out your lint filter.

Make it so your dryer's automatic cycle dries your clothes properly | Reddit