Why can't I select my Twitch Prime Loot from GTA 5 online to GTA 5 PC?

I can only choose Playstation, X-Box & Stadia. Or will it be credited to my GTA 5 PC account for the current screenshot in 7-10 days because there's a checkmark below for confirming that I played the introduction?

You don't have to link the PC because the PC is already linked through the Rockstar account. You should go back to the Twitch Prime page and claim the loot.

I've already claimed the loot.

Nice.