Odyssey tailgate won't stay closed

I have an 04 Odyssey that out of nowhere, the tailgate would not stay closed. What I mean by that is even if you slam the door shut, it won't latch. The power lock still move up and down when you use the keyless remote and /or lock switch. I had to use straps to keep the door closed so we could drive it. I tried adjusting the latch that is attached to the bumper and it still won't catch and hold it. Any info is appreciated. I can only find people that can't get their door to open. This is a manual opening door.