Horses Die After Putting Saddle On

Earlier today I started playing on my phone. I opened up a world and tamed a horse. This horse was at full health and in an open pasture. The little hearts came up as normal and I put a saddle on - only to find I was dismounted and the horse died, leaving the saddle behind. I was confused and left the game, restarting it before joining. Upon entering, I tried it again. This horse had a higher HP - like 11 hearts or something - this time the horse lost all but one heart. I continued to try and found the horses with around 13 almost never got hurt or died. There were some exceptions. I was able to put amour and stuff on but saddles were a no - no. This also happened in all my other worlds and I was not able to resolve it. I'm not sure what this is but please fix it!!