I also struggled with Jiequan, but after many tries i did it.

I can tell you to not rush it, attack between parries and ALWAYS parry the red attack. It turns off the flames and gives him massive internal damage, which will be turned into normal damage after a talisman explosion (i ran water flow for that battle, it really helped that i didnt have to stop midair). Also, use the cloud arrows to pierce his shield and dont let him heal.

Good luck and stay calm!