I am tearing my hair out trying to solder a few STS pegs onto a STS bangle/cuff (which beads are going to be glued on).

I am quite new to soldering but thought I had it sussed. I have been using solder paste, I can see it try to flow, but then it just seems to dry out and do nothing else.

I have tested solding anther piece..fine.
I have melted solder on the pegs...fine.
I am sure that the bangle is clean and the holes the pegs go in.

What's going on???????