UnexpectedTypeException - entering product preferences

[Leo Knudsen]

Hi there.

Im currently working on a Prestashop 1.7 (1.7.4.2)
im experiencing an error when entering product preferences in my backoffice.

i have been trying to find a solution for a while now.
the only answer i find is that its fixed by a new build of the 1clickupgrade v4.0.0-beta if im not wrong

or a solution with some language configuration for config keys: PS_LABEL_IN_STOCK_PRODUCTS and PS_LABEL_OOS_PRODUCTS_BOA

Nothing have seemed to work for me so far.
im using a custom builded theme from Leo Theme (Leo Fresh Farm theme)

im not sure what to do to fix this issue anymore
im searching for some suggestions to fix this issue.

Thanks :)