Check my throttle linkage

How much return spring load do yo have?
Is this a throttle return spring?
upload_2021-4-9_16-17-46.png

And two more here?
upload_2021-4-9_16-21-11.png

Maybe try with just one spring but in the top hole of the bracket.

My 3310 has some downward pull on it and it's just fine. Your cable pin looks somewhat closer to the throttle shaft and more forward than mine. Raising the cable bracket should help I would think.
upload_2021-4-9_16-32-9.png