Assertion error expending cookie

[Jidarofa]

Hello I have the follow code

it("it should gives the token", (done) => {
			var agent =  chai.request.agent(url)
			agent
				.post('path')
				.set({
					"Content-Type": "application/x-www-form-urlencoded",
				})
				.send({
					"username":"user",
					"password":"ps",
					"domain":"ForAllDomains",
					"authMode":"user",
					"state":"",
					"__oauinst__":""
				})				
				.end((err, res) => {
					expect(res).to.have.cookie('.BzSSO')

But when i want to have the cookie is't possible because appear the next error:

Uncaught AssertionError: expected cookie '.BzSSO' to exist

real response:

headers: {
    date: 'Wed, 18 Aug 2021 16:46:40 GMT',
    'content-type': 'text/plain; charset=utf-8',
    'content-length': '155',
    connection: 'close',
    'cache-control': 'no-cache, no-store',
    pragma: 'no-cache',
    'content-encoding': 'gzip',
    expires: '-1',
    vary: 'Accept-Encoding',
    'set-cookie': [
      '.BzSSO=CfDJ8KfvN9uUUfFEqXxmsdwgrYPk07XJVYGFBc_fIVMPwSFgPm01pvGfUt4rBsDdhQIo3hpsY8HpN30ag7PstNz9rMbthHmD__a7G7DZrHcip9yoO21KnXgNKZrIDpGWr_7zjwC8fL-hY8ETNcSDwy-jYAMW2TE-mHOcGWoHIiJWj7TopzobnDKMFHlPSvyLk6WfSC_iIb0XOePNGQVLW0wGNlutxAYXYmYjtGdmrrFGWrk09JqxAZHdbWxkjeX5qmJro7OITOjJY0EfJopdE3pZH4oL089SKhpv2f1syRutVI__jbYjWw6CDY3eyy98BY; expires=Sat, 28 Aug 2019 16:46:40 GMT; domain=accounts-cuaderno.bizagi.com; path=/; secure; samesite=strict; httponly'
    ],