Help with liner

I'm really getting frustrated. Installed new liner. One of those that is made to work on beaded or J-Hook type installations. I've got a J-hook and the new liner, it seems like the hook is longer than the old liner, and doesn't fit in the track as well. Anyway, tried filling the pool, got it about 1/3rd filled, when the liner walls just started falling, all the way around the pool. After it drained, replaced the washed out sand, and used the foam cove molding stuff (thought maybe I didn't have adequate coves with the sand.)

Got the liner hooked back up, and got the wrinkles worked out without too much trouble. Started filling the pool back up. Got up to just about the top of the cove, and the liner pulled down again. All the way around the pool. So now. I'll have to replace sand..again. and alot of the cove stuff has managed to come loose from the wall, so I need to put that back into place. If I can.

What am I doing wrong? The pool floor is flat (more or less) and is the same as it was before I had to replace the liner. I'm spending way too much time and money trying to get the pool back together.

Should I try duct taping the liner up until its filled with water? Would that even help?

I replaced the liner once before, and never had this issue.

Thanks

You could try some large spring clamps to hold it in place till it is done stretching, I think that may be the issue, as you are filling instead of it stretching it is pulling out of the bead.

Thanks for the tip. Elected to do binder clips instead of clamps. They're cheap, and they actually fit into the channel with the J-hook of the liner, so they wedge it in more tightly.
They work way better than duct tape, which tended to let loose, and leave adhesive residue.

Using the clips, I was able to hang the liner by myself with relative ease. Left the clips on until the water was starting to flow into the skimmer. Filled it with a garden hose, so it took quite a while to get there. Took the clips off with lots of apprehension, but the liner has stayed up. Thanks.