Food Scale issues??

Hi all.

Finally bought a food scale to track calories however it is already in accurate.

I tested the serving size of a few products and it is slightly inaccurate which I know its epexected but other foods I tested are widely inaccurate.

I weighed a serving size of peanut butter and what looks like a serving or 20g is like 5g??? Any issues to fix this?

Unless im overthinking. Any advice would help.