Your description is not detailed enough to help you here.
What does that mean? Are you connected (wifi, ethernet are up have ip, dns is set)?
Why should it be?
I have to admit I do not know anything about gufw, but for what I understand it is just a gui to ufw.
Is ufw set to be persistent, and what rules are loaded?
Next question:
since 10.0 PureOS comes with firewalld enabled by default. Is firewalld still running?
$ sudo systemctl status firewalld
And since firewalld is running most likely anyway, do you need gufw?
firewalld in its default initial configuration does exactly what you are setting your gufw to.
-H