VFB Pro ignores max length for spam

Hey,

since VFB Pro is very bad at filtering spam i build 2 honeypots.

Both fields are hidden and I test if the fields have a length between 0 and 1:

https://ibb.co/XbtKNhy

When I test it manually its working fine. But it does not stop bots form spamming me although they are filling the field:

Field filled with a number
Field filled with spam

Am I missing something or is the plugin not working properly for automatically filled input by bots?

Cheers