This is happening to mine too, hope you get an answer:-)

Me too :-(, only cutting them to stop them setting seed pods.

Don't know if this makes a difference or not, but it's the ones I'm growing with dwarf beans in a tub - happily the beans are producing lots of flowers and beans. Variety is bouquet mixed and it does say flowers on long stems.... As long as the beans are ok, but I won't do this next year. Incidently my Old Spice sweet peas in the ground are flourishing on long stems.

Mine are in large pots, regularly fed and watered and the first 5 vasefulls had longish stems, the new ones are short. Still they look gorgeous and smell divine, maybe we could float them in a bowl lol:-)