Should I Keep or Sell my Crypto Rewards from Revolut’s Quiz Feature?

I recently used Revolut’s feature where you can earn crypto rewards by answering quizzes. The total amount you can get is capped at €15 (~$16). The rewards are split across different cryptos like Cronos, Floki, SEI, BONK, Sui, Oasis, and Polkadot.

Right now, I have €15.89 (~$16.80), so I’ve made a small profit of €0.89 in about 4 or so days. But I’m not very knowledgeable on crypto and only have a surface-level understanding. My question is: should I hold onto these cryptos, and if so, for how long? Or is it smarter to just take everything out now and get my free €15?

I know this small gain doesn’t mean it will keep growing, so I’m trying to figure out the most practical option. Any advice for someone in my position?