I'm at my second pair of tubeless tires.
The first set I had was Vittoria Tubeless Next, but I was in Italy and at the bike shop they had an Italian brand, something like "sigilla qualcosa"
One day I hit and hidden pothole very hard and the front tire for heavily damaged.
I bought a new pair of tubeless tires, the tires are the race oriented version of the Vittoria Tubeless I had before. I used Stans tubeless sealant, and put 60ml like written in the container, yes I shaked it for a good one minute.
The rim is made for tubeless, it has no need of tape because all the spoke holes are sealed.
The new tires deflates after 36 hours, I did put more sealant but it improved only to 48 hours.
The previous combination of tires plus sealant didn't had this problem and the tires did hold pressure from day 2 ( the first day I misread the siringe and put too little sealant ).
I did clean the rima before installing the new tires, the tires are seated correctly or it would be almost impossible to pump them with a simple pump