Repetition structure does not work when my object is copied without reference

I need to remove an attribute from my object (indexvariance attribute), but I need it to stay in the root object.

This is my algorithm that receives in the variable my object variable and then I remove the indexvariacao attribute attribute of the object, in this way the algorithm works perfectly, but apart from the variable variables, it is also removed from the variable categoryForm:

    var variacoes = categoriaForm.variacoes
    if(variacoes[0].estoque_variacao == null || variacoes[0].estoque_variacao == 0){
      variacoes = [];
    }
    //Retira do objeto o indexvariacaoatributo
    for(let i=0;i<variacoes.length;i++){
      for (let j=0;j<variacoes[i].atributo.length;j++){
        console.log(variacoes[i].atributo[j].indexvariacaoatributo);
        delete variacoes[i].atributo[j].indexvariacaoatributo
      }
    }

  console.log(variacoes);

I tried to make a copy without reference of these forms:

var variacoes = Object.assign({}, categoriaForm.variacoes);

I've also tried:

var variacoes = { ...categoriaForm.variacoes };

But these two ways, when I start the variable variation I realize that my index is still there. I put that console.log and I noticed that it is not entering inside my for.

Is there anything else that needs to be done when copying an object in this way?