Same issue here. This thread was opened in 2019 and has 100's of people saying the same thing. This is clearly a bug and should be looked at. If it doesn't get fixed then it just means they don't care. much about this "feature". The company clearly doesn't care about this since they want you to spend money on Sacred Shards, not get them for free by having other people play the game. 

2021-02-14 same problem

2021-05-20 not working :p

Same here pls help

I have also tried making the referral work but my account just does not seem to get the rewards after 5 of my friends tried creating the new account through my link

UID - um41476995 | 40650031

i got a friend to start playing using the link and i wanted to no y is he not getting the rewards like me i get them as he levels up and is now 20 i have got the rewards but he has not any help to fix cuz he is getting mad thinkin it is just 1 sided my name is ratedrpsycho his name is frapp attack

This is still on going? I gave my wife the link, we both play, she is now level 21 and still nothing from the link.

reffered  2  friend  both  lvl  30  and  still  doesnt  work

I'm going to close down the thread from 2019. It's a lot to try and help from. If you have have a referral link not working, please open a support ticket HERE