You need a separate wallet fpr amethyst i use minibits wallet

If you hold down the zap button it will open up a screen where you can connect a wallet via most wallet connect, otherwise when you try to zap it should launch your default wallet app

if you were using Primal most probably you are not that into testing beta wallets cashu mints, etc...

I would suggest you consider Wallet of Satoshi as your default wallet for LN⚡, you add it in your profile as the wallet to receive zaps and to zap people, just push and hold the ⚡zapping icon and add the usual amounts you like to zap, 21, 100, 1000, 10K, etc, do nothing more,

When you are going to zap, just click ⚡, the app will open any LN capable wallet you have installed, if only WOT, choose it, the invoice will load ,just pay it. minimal fees or none.

One more cool thing, when setting the amounts you can choose how you want your zaps to be: Public, Private (only you and the receiver will know), Anonymous (nobody)... Amethyst is full of cool featured

If you are not into new tech testing, I will suggest you forget about NWC, that is for beta testing wallets with Cashu and NWC (network wallet connect), if you are not curious stay away, is fun, but you will lose sats for sure, everyone testing does.