Registration/Login Forms Errors

I have just installed Ultimate Member on my website, but can’t seem to get any of the forms working (registration, login,etc). I have tried deactivating plugins, changing themes, etc. But nothing. I was about to delete it, but I decided to consult with you first. The site is located at: http://www.buyerznet.com.

https://ww.wp.xz.cn/plugins/ultimate-member/