Have you checked that its not your drivers needing to be updated or reinstalled?

That fixed the clicking issue, Unfortunately it still has no pressure sensitivity.

Strange I guess I did need to update my drivers.

Wait did, you close SAI and reopen it?
Also try going to Wacom settings and reset them.
But before that, turn off your tab and unplug it and take the battery out and then put it back in and now try :)

Wacom pens don't have batteries.

But the tab does that you are using it on? Sometimes that can affect it

nah it's connected with a USB

Do you have a Wacom Desktop Centre? If you do click on Backup & Restore Settings To Computer & the Reset Settings.
You lose all your shortcuts sadly so will need to reconfigure but doing this fixed it for me then I Made a backup of my settings once I set my shortcuts again for if I ran into issues again. But this was the fix to my pen pressure, I hope it works for you :) If you have those options :)

I re installed the software and restarted my computer and it works now (Had to completely uninstall software too)

Glad you got it fixed :) Setup the shortcuts and backup the settings in the Wacom centre :)

Glad to help :)

Awww yee, yeah it was a passing thought to re install my tablet soft ware but I was like NAH it was the water man.

XD Thats alright, I've had it happen to my tablet so I thought I'd suggest it. Glad everything is working properly now :D

But I'm pretty sure this is to do with the panel settings, happened to me and once I reset them, it worked fine :)