Are you burning DATA to the DVD or are you burning it as DVD (VOB) files? Have you tried playback in a different player?
Does it play on your PC's optical drive? If using Windows 10, you might test burn as an ISO file. Then right-click and open that file with Windows Explorer. It should appear as a drive letter - a virtual disk.
Have you tested a different brand of media? Burning to a CD/RW (re-recordable) will save disks, until you're certain that all is well.