Hi all really need to pick some brains

I've got pretty much stock rst s2
Ony as a chip ecu and t3 turbo with 360 roller bearing and a exhaust

I've just had a full stage 1 clutch kit fitted brand new quadrant and cable so all new there

But the clutch is slipping at low boost of 7 psi the flywheel looks mint

As anyone else had the issue or have an idea what could be the issue as I'm a little stumped lol any advice would be great many thanks