Hello
i have purchased Pico 8, clicked the e-mail, logged in to humble but there is no Key showing up. On lexaloffle is also no "Product" or key in my Account.
Where can i find my key?!

https://www.humblebundle.com/resender

right above the key entry field

When I logged into Humble after purchasing it, it said something like "This has already been claimed by user".

But I can't find a key for Pico 8 in my Humble account

Click the link I gave, scroll down to pico8, click it, and the key should be on the following screen;top is a video, middle is account activation url and key, and the bottom is humble hosted files

No pico8

Start clicking those, if it's not in one of them then you do not own it as far as humble is concerned

I censored my old key, but it definitely doesn't say my old key is invalid as humble can't confirm keys thenself if it's redeemed on another site

This is showing up when i open the pico8 email i got after purchasing. But it is definitely not my own humble account.

Might be time to take it to humble bundle support or DM them on Twitter with transaction proof