I sold a new Riva SE kit with Liberty flights liquids PV 8 mg nicotine , after 2 weeks vaping i called him 1 hour ago to ask him how's going on , he told me that he sold the Riva kit and went back to analogs because he was getting sudden dizzy and lots of heartburn , what's going on ? i told him everything how he must use the e-cig and i told him from the start to vape slowly and not fast vapes at the start and i also i told him to drink water and all other important steps , he says he made everything i told him and that didnot prevent the heartburn and dizziness , i kinda feel bad that he suffered because of me , that was the last time i recommend the e-cig to my friends , i am still vaping because i smoke non nicotine liquid and i dont vape too much , only with coffee 2 or 3 times per day thats all, i had no problems like he did , any advice ??