MongoDB / mongoose / Express - problem with adding Array of Objects


I’ve been trying to add an Array of Objects to my Product model schema but I get an error

CastError: Cast to Array failed for value when trying to save a model that contains a model...

and I noticed that items inside array for ex. “specifications” array behave like described below…

I send data from React component state like this

specifications: [{
   value: 'some value',
   label: 'label name'
   value: 'some other value',
   label: 'label other name'

but In Express server I have data like this:

specifications: '[object Object], [object Object]';

and I can’t figure out how to solve it. Anyone knows how to approach the problem?

File with model Schema —>

File with the route -->

Compoenent in which I send post request with data —>