undefined local variable or method `params' for controller

I am trying to implement contact manager with rails. I am using RSpec for test-driven development.

"When I am looking at a single person’s page, I click an add link that takes me to the page where I enter the phone number. I click save, then I see the person and their updated information"

I am trying to validate this action.

In my controller class

describe "POST #create" do
context "with valid params" do
  let(:alice) { Person.create(first_name: 'Alice', last_name: 'Smith') }
  let(:valid_attributes) { {number: '555-1234', person_id: alice.id} }

  it "creates a new PhoneNumber" do
    expect {
      post :create, params: {phone_number: valid_attributes}, session: valid_session
    }.to change(PhoneNumber, :count).by(1)
  end

  it "redirects to the phone number's person" do
    post :create, params: {:phone_number => valid_attributes}, session: valid_session
    @phone_number = PhoneNumber.new(person_id: params[:person_id])
    expect(response).to redirect_to(@phone_number.person)
  end
end

I want to redirect to phone number's person but while getting phone number It gives me an error undefined local variable or method params' for #<RSpec::ExampleGroups::PhoneNumbersController::POSTCreate::WithValidParams:0x00007fc89e276898>

I also have view test as follows

 it 'adds a new phone number' do
  page.click_link('Add phone number')
  page.fill_in('Number', with: '555-8888')
  page.click_button('Create Phone number')
  expect(current_path).to eq(person_path(person))
  expect(page).to have_content('555-8888')
end

Right now this test is also failing because of this error :

expected: "/people/1"
got: "/phone_numbers"

How can I resolve these problems and redirect user as desired? Thanks in advance