Give it some more time on those side shoots so you have a bigger chunk of plant matter to work with.
It's easy to break small weak young branches like those.
And the more nodes you have under the rooting medium the more potential root development sites there are.

I wait until the shoot I'm interested in cutting has at least 4 sets of leaves plus the growing tip:

Leave the growing tip
Leave 2 more sets of leaves
Slice off the rest cleanly with a razor blade