I'm still trying to find answers, but as it is now, the default referral links do not work.
Users trying to join via referral links receive an error and will not be able to sign-up.
Use alternatives
Make sure to change your links to an alternative wallet/faucet
Example:
OpenLedger: https://openledger.io?r=fav
Rudex: https://market.rudex.org/?r=fav