I only use 1 wallet, why is it that when I receive the reward it says connecting another wallet without me knowing that wallet?

I had something similar so I had to import my Warpcast seed phrase into wallet to claim. I wasn't able to claim through my connected wallet but it worked with Warpcast seed phrase. 
Import your warpcast seed phrase into wallet and claim, it will work.

Go to settings (Warpcast settings) > Advanced> Reveal Seed phrase> copy this seed phrase then go to Coinbase Wallet Or any other wallet and Import this seed phrase there (make wallet with seed phrase from your warpcast account) then connect this wallet to build website and claim token.