Why can't I catch Uxie?

I am fighting Uxie, I have his health in the red and he is lvl 50 where all my Pokemon r lvl 51 or higher. I have used 9 Great Balls, 9 Net Balls, 9 Nest Balls, 9 Ultra Balls, 9 Dusk balls (2am here), 9 Timer Balls, 9 Quick Balls, 9 Luxury Balls, 9 Heal Balls and 9 Repeat Balls. The most I get is 2 shakes of the ball then it breaks free but mostly 1 or less shakes before it breaks free. Why can I not catch it?

Pleaselog inorregisterto add a comment.

All pokemon have a percentage that determines how many times the ball will shake, or if the pokemon will be caught. Most legendaries, including Uxie, have a very low catch rate and are a challenge to catch. I’ve had trouble catching legendaries, such a Mewtwo in Heart Gold. P.S. Don’t try to do a Chuggaconroy and used Pokeballs that don’t work well on legendaries, such as the Net Ball and Nest Ball. Also use you’re Timer Balls last, so that they can get a higher chance to catch Uxie. Hope this help!

Just being in the red is ok for most pokemon, but for legendaries, try using false swipe to get it down to 1hp and sleep powder/spore etc to put it to sleep, that’s the best case scenario