I was charged a fee of more than R$5000 for the support plan on azure that I did not request

Guys, I recently created a free account on azure, and I was trying out some of the features, and apparently I activated a support plan that I didn't even receive or receive. Didn't even know I did it. but now I received an invoice for more than R$5000. How do I explain to Azure that I don't use it or if I requested the support plan, was it by mistake? Thank you very much in advance.