Guild Wars 2

I have a beta slot, and a portal stone for the beta, but for some reason I can’t create a character

Same issue here.

Though I also want add an extra question to ask, we can only beta test once out of the available times?

the beta is not up currently, 2nd part will start in 6 min from this post

You can only create a character while the Beta is running. So once 3:30 PST hits, you can create it then.