Desperately need help with FLAVORING!

Hi guys…trying to concoct a blueberry green tea here. So far I’ve blended gunpowder green tea with dehydrated blueberry bits and Lorann’s Super Strength Blueberry flavor. I’ve used quite a few spritz of the flavor (put it in a small glass spray bottle) and I don’t taste ANY blueberry. Is there another brand of flavoring anyone can recommend? I know people keep these things hush hush bc it’s part of their ‘secret recipe’ but I just need a brand recommendation here… TIA!