Having trouble redeeming a bundle, tried multiple websites.

I'm trying to redeem the Leartes Unreal and Unity Assets Giga Bundle Encore bundle but every website I've tried it hasn't worked. Considering a bunch of people bought the bundle I'm wondering how you guys figured out redeeming it. I've tried Epic Games itself, which I figured wouldn't work in the first place.

I tried this website that Humble links to redeem the assets but when I press 'get' nothing happens, it doesn't tell me anything, I just stay on the same page. https://leartesstudios.gumroad.com/?section=2tAc2gzPSAGPOUydM6y40A%3D%3D

I tried the Cosmos website but when I go to search for the asset it doesn't pop up. I think this is my best bet but it isn't working. https://cosmos.leartesstudios.com/

In another similar post someone recommended this YouTube video, but I can't get to the step he's at since I can't find the assets I bought on Humble. https://www.youtube.com/watch?v=yXEXZsmGweQ&t=316s

If anyone has figured it out that would be super helpful. The bundle looks awesome, I just can't get to it. Thanks.

Edit: Finally figured it out. For most of the bundle you click the link, which goes to Gumroad. At checkout the coupon should automatically be applied most of the time, but you have to manually enter in zero dollars for tip. So yeah, all that time and I was just stupid. Some of the other links go to the Cosmos website, and for those you just go to redeem and enter in the code. In Cosmos once you enter in all the codes you go to library. You then have to click on each and every one of the products and in the bottom right press get redemption code for UE. A few of the products can't be redeemed on UE, but that's fine. And there you go. If anyone else has a problem it shouldn't be too difficult now. Thanks for the help.