Zwift Hub - MTB boost 148 - Not enough space between frame and cassette

Hello Zwift people!

I am facing the following problem.
I have a Zwift Hub with a preinstalled 12-speed cassette, I plan to ride on an MTB with a 12x148mm rear axle. I have put the proper adapter, the green one on the left side of the hub, and the larger silver one on the right. Now, when I install my bike on the Zwift trainer, the cassette cannot move since there is insufficient space between the cassette and the frame. Measuring my rear normal wheel, I think I am lacking around 3/5mm of margin… Am I missing something? Should I mount some other spacers?

The 12 speed shouldn’t have a spacer behind the cassette. You could check if one was added by mistake during build. Ideally some pictures would help.