I kept spawning by the side of bed and falling to my death

I built a mini game with beds and spawning and it suddenly stopped working and I kept spawning next to block and falling very far and dying. It started happening when I placed my bed. It has happened in many of my worlds in almost every one it has happened.

 

I can't send the video to you because of the limit. Contact me if you want a video of it, the video shows a lot.