Hi again! 
Ordered a couple boxes of KR808 carto's from KR808D-1 Cartomizers (Use with DSE901) - in addition to a few bottles of liquid from Good Prophets.
No matter what liquid I use, I can't seem to get any flavor with my vape. Specifically, the Wintergreen from GP tastes like literally nothing at all. We are using Riva 901 batteries with these carto's.
I have also tried several we have from Vixen Vapors, and those flavors have now turned rather muted as well. The carto's also seem to hold on to old flavors, (e.g. one fill with an Almond Joy-esque liquid, then a later full refill with Banana Split = still tasting like Almond Joy). This also seems to be the case now with liquids from E-Smokey Treats, too. Nothing tastes nearly as good as it did before we got these, and usually you can't even tell what you're vaping.
Am I doing something wrong? At this point it seems to be just wasted money in search of the "perfect" e-cig and liquid. I know it can take a lot of tries to find out what works best, but this is getting ridiculous.
Here's the mixed percentage & flavors, if it helps:
EST: 50/50 VG/PG - Cinnamon Bun, Cherry Cola, Blackberry
VV: 40 VG/60 PG - Banana Split, Almond Ahoy, Pralines & Cream, Blueberry Cotton Candy
GP: "Flavorfulls" - Wintergreen, Peach Pie, Cherry Vanilla (not sure on the %.)
Thanks in advance.

Ordered a couple boxes of KR808 carto's from KR808D-1 Cartomizers (Use with DSE901) - in addition to a few bottles of liquid from Good Prophets.
No matter what liquid I use, I can't seem to get any flavor with my vape. Specifically, the Wintergreen from GP tastes like literally nothing at all. We are using Riva 901 batteries with these carto's.
I have also tried several we have from Vixen Vapors, and those flavors have now turned rather muted as well. The carto's also seem to hold on to old flavors, (e.g. one fill with an Almond Joy-esque liquid, then a later full refill with Banana Split = still tasting like Almond Joy). This also seems to be the case now with liquids from E-Smokey Treats, too. Nothing tastes nearly as good as it did before we got these, and usually you can't even tell what you're vaping.
Am I doing something wrong? At this point it seems to be just wasted money in search of the "perfect" e-cig and liquid. I know it can take a lot of tries to find out what works best, but this is getting ridiculous.
Here's the mixed percentage & flavors, if it helps:
EST: 50/50 VG/PG - Cinnamon Bun, Cherry Cola, Blackberry
VV: 40 VG/60 PG - Banana Split, Almond Ahoy, Pralines & Cream, Blueberry Cotton Candy
GP: "Flavorfulls" - Wintergreen, Peach Pie, Cherry Vanilla (not sure on the %.)
Thanks in advance.