BIAB flat beer - using dextrose

How much priming sugar did you use for the flat batch, the amount of beer you primed, and what is the temperature you are holding the bottles at? (I read through all of this, but didn't see the exact amount and temperature, so please excuse me if it's a repeat. I just want to make sure I have the facts).
Hey Yooper,

No probs mate, it's tricky when it's a long thread, Appreciate you taking the time to help.

I used 200 gm for 14 litres of wort (think that translates to 7 ounces and 3.5 gallons) and they were held at 24 C degrees (75 F) in a temp controlled chamber for 2 weeks.

Here's an interesting note. if I turn a bottle upside down for 1 hour (that's been in the fridge for a few days) it gushes like crazy when I open it.
Sounds like it carbonated to me! :D
Based on the sugar amount and volume, you overcarbonated the h*** out of it! I generally use 4 to 5 ounces in a 5-gallon batch. One thing I think we can eliminate is the leaky cap hypothesis....