Here's one I ran into, did you buy a new tow vehicle with the self leveling rear end? Don't laugh I seen it happen.

Have encountered a few steep ramps where the best bet for our boat you have to run the boat nose up just barely short of the roller, hook it up to the strap for safety, then pull the truck up a foot or so to change the angle and get the nose above the roller then run it right up all the way and crank the strap tight.

I had the same problem when I first bought my boat. 90% chance you are putting the trailer too deep as others have said. I mistakenly thought the deeper I put it in, would help it. Not correct as least for my boat. As far as saying you tried really shallow too, sometimes if it is too shallow you cant get enough of the boat on the bunks to get the bow to lift making you think you are having the same problem. Start a little shallower than normal and push the boat up on the bunks as far as it will go with the motor, then back it in a few inches, not feet and try again. When you get it up close to the roller you will have an idea of about where it needs to be. My boat is different for every ramp depending on how steep the ramp angle is. The steeper it goes the less of the trailer I put in the water. Hope this helps.

first boat? how old are you?

I'm sure every boat may be a little different but with mine, if I have the trailer too deep in the water this happens. If I bring it out a bit then the nose goes right on top of the roller. This might be capt obvious but I put the trailer in further to launch than I do to load up. I'm sure you'll figure out what works best for your rig. Good luck!

Back in get the boards wet, then pull up some. I know on mine when the front of the fender is exposed out of the water a couple inches and my 2 middle boards are well exposed it slides right on. Sometimes got to goose it a bit to push it up further.

Sounds like the trailer was too deep.

Let your center rails on your trailer be your guide,leave the front edge of the rails slightly above the water line it will go on there perfect every time. It won't make a difference what angle the ramp is, it will hit the rails first and automatic lift the front of the boat and put it above the roller every time.