Hi Wilma,
Generally, when you lose the color carrier, it's cable or connector related. I'd first do what Dave suggests. Unplug, then replug the video cable (usually a yellow connector). Do this at both ends (DVD player and TV).
If that does not fix it, try another video cable. If that does not fix it, using another video cable, try another video input at the TV, if there is one - just to test it.
It is possible that the video output section of the DVD player is going haywire on you but my money is on the video connection/cable.
Jim