Moserbaer LiteOn DH-20a1p DVD R/RW/RAM can read cds and not dvds

Please someone help me
My DVD was working fine but suddenly it doesnt read any dvds. cd works fine but no dvd. When inserting a dvd it makes a sound and stops.nothing happens. i have tried to reinstall the dvd & clean the lenses but nothing good so far.It would be great if all u would tell me the solution.:bow:
Thanks in advance!

-DSW