DVd Drive Reading CDs only not DVD

Hi There…
my LG DVD drive is only reading CDs but not DVDs.
hl-dt-st dvd-ram gsa-h55l

some times (rarely) it reads the DVDs it writes (also writes rarely)

how to resolve??

Your dvd drive has two lasers, one for cds, one for dvds. It sounds like the laser for the dvd is dying. You could try cleaning the lens, but it may not help.

It may simply be time to replace the drive.