RBGPOE - Technical Details and Functions

I bought two RBGPOE from an Italian reseller.

I am using two of them in the same configuration, since they are said to be passive poe

power → RBGPOE (as injector) ------> RBGPOE (as splitter) → power
data → → data


I assume something is wrong, since my device will keep rebooting. Cable lenght is 25mt

try to use 24V, 1A PSU,

What board it is ?