I still don't see my referral code. It's been 3 months since I received my car.
If you really need one to use, give the customer service a call and tell them you are a Model 3 owner and know a potential Model S/X buyer and want to refer them but you don't have a code yet. I became an owner May 30th, didn't have a referral code, and my brother was about to order a new Model S and I wanted to have him get free Supercharging. Called them up and told them my issue, got put on hold for about 10-15 minutes, and then the dude was like "It should pop up on your account and I'll e-mail you the link, but you can write this down if you want it now....oh wait, there it is, should be on your account." Sure enough it popped up on my Tesla account on the webpage and then the loot box appeared on my app. Sent the referral link to my brother and everything worked out great. He gets free supercharging and I should eventually get a nice black wall connector.