Are you sucking e-liquid (what we vapers typically call "juice") into your mouth, and, if so, are you swallowing it? The problem of juice entering your mouth can happen if the e-liquid is flowing faster than the rate at which it evaporates, so that the chamber gets flooded and gurgles as a result. Often times, sucking less hard can turn out to be the solution that works, but there are a lot of cheap pod systems out there that simply are garbage so there might not be a solution. Either way, if you are constantlly swallowing juice, then you need to stop. Anything more than just mild "spitback" (a thin spray getting mixed into the vapor only just a little bit) going into your mouth can be enough to upset your bowels and/or can tend to make you feel like you want to gag─especially if juice gets boiled repeatedly before it cools back down again so it turns to crud that gunks up over time instead of immediately turning to vapor.
That being said, pod systems are not for me. I can understand the appeal, but IME they don't satisfy me even if they work right, whereas other people swear by them. There is no "one shoe fits all" in vaping, and, a lot of vapers, even among the experienced, seem to underestimate this fact─a whole lot actually. For a lot of us, being able to tailor the vape experience to our own personal preference is more than just preference. Wrong choice of vaping hardware or wrong choice of juice can, and very often does, turn a person back to burning tobacco. Look into rebuildables (start with an RDA) if nothing works, or if something does work, then still consider looking into rebuildables. (Personally, I, not only picked up vaping by jumping head first into RDAs, but at the same time also I managed to switch from smoking 16-17 Marlboro reds per day for more than 20 years to vaping in this manner, which took only 2 minutes to do the switch... permanently.)