Hi @Bac_Nguyen,
These forums are pretty much populated with people who already own an Anova. Historically I’ve seen many people post that they have been very happy with their interactions with support. (I’ve never had a problem with either of my APC’s so I’ve never needed to contact support myself.)
Did you try any other support option? Web? Email?
The support email is support@anovaculinary.com
They also have a web submission option that can be found on this page: https://support.anovaculinary.com/hc/en-us
Even if you’ve returned the Anova I highly recommend you still look into cooking sous vide. You can prepare some things using sous vide that you just can’t easily duplicate with any other method.
Best of luck.