Handbrake not working

[a22nec]

Been having a problem with the handbrake on my car which is simply not working on steep hills.
The right caliper was slightly seized which seems to be a common issue on all cars that have these calipers.

I rewind the pistons, bought the return springs, changed the brake fluid but it's still sticking very slightly before it hits the bracket stop limiter.

Readjusted the handbrake until it lifts off the limiter by 1 mm.
Now it's even worse, the equaliser is not flat, it's slightly angled and the handbrake does not stop at all on steep hills.
As I had to go MOT, I was hoping for it to fail and check which caliper is not braking but turns out it passed with 1 percent difference?? How ?
I've checked the cables and they seem fine with no damage and the brakes are working correctly when applied by pedal.

 

[RUM4MO]

I’m guessing that the sticking piston is now back out in it’s original position so it is sticking again.
If the pads are “well worn” replacing them with new thicker ones will force that sticking piston to now be in a “cleaner” position - although this is just a work around and not a proper fix. To fix that issue properly will require you to remove and clean the piston and fit new seal and dust cover etc.
When that happened to my wife’s 2015 Polo, it was properly seizing so I replaced it and the pads.

 

[a22nec]

I replaced the discs and brake pads 2 years ago.
The car hasn't been driven much so the brake pads are still fairly new. The old ones were almost to the iron on the right side because it was seizing.

This has happened before on another Ibiza but just by installing the return springs it solved the problem.
This one is giving more headaches.