This is a two fold problem. Firstly, harnesses are not great. They are as different as we are and therefor fit is individual. Some like structure, some like flexibility etc. Finding one that doesn't ride up on you personally is a matter of trial and error, and its pretty hard to tell from just putting it on and leaning against a wall mounted bar in the shop.
Secondly its rider error. If you fly with your kite up high all the time there is no where else for your harness to go. A seat harness will only succeed in giving you a wedgie. Learn to bring the angle of pull a little lower and you will help out your cause.
Can you please enlighten me with some harness that doesn't goes up on chest and make it impossible to take a breathe.
I use an old Cabrinha Harness and I tried Mystic Majestic 2013 and both were killing me.
May wind be with you all.
The harness riding up is down to your poor technique. You're a beginner so you can't expect much more.
You can switch to a seat harness while you're a beginner if you want. You might experience the odd nut crunch.
Better to get better at riding sooner. Ride with your kite a little lower. Straighten your back and push your hips forward. Straighten your arms and steer with shoulders and upper body. Don't work the bar by bending so much at the elbows (that will give you tendonitis.) Straighten your front leg. Bend you back leg slightly. More weight on the front foot and engage the rail. Don't over edge and stomp the tail (unless you're super powered up and going for a boost) etc etc etc