Here's a whole run through of what you need to do ;)
For each pair, you need to condition them outside of the spawning tank for 2 weeks. Make sure they cannot see any other betta beside their partner. Are these pet store fish? They may be too old to breed. I suggest getting some IAL to induce spawning. With spawning the tank should be 80-82*F. Also, your nest may have popped due to the atmosphere not being humid enough. Place half of a foam cup as a placement for the male's nest. Then either have a tank lid or plastic wrap around the top of the tank to keep the atmosphere humid enough that the nest will not pop.
Recondition the CT and VT pair and try again. Sometimes bettas do not like each other, so you may have to get new partners or pairs.
Hope I helped :)