JWT Token not expiring - asp.net-core-webapi

Question

I'm working on .net core api 2.1, I have implemented JWT token authentication, I want jwt token to expire after given time, but it is not expiring. Token still validation even after expiry time.
Startup.cs code:
// configure jwt authentication
var jwtSettings = jwtSettingsSection.Get<JWTSettings>();
var key = Encoding.ASCII.GetBytes(jwtSettings.SECRET);
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(x =>
{
x.RequireHttpsMetadata = false;
x.SaveToken = true;
x.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = false,
ValidateAudience = false,
ValidateLifetime = false,
ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(key),
ClockSkew = TimeSpan.Zero
};
});
services.Configure<IISOptions>(options =>
{
options.AutomaticAuthentication = true;
//options.ForwardClientCertificate = true;
});
SignIn api code to create token on sign in:
var tokenHandler = new JwtSecurityTokenHandler();
var key = Encoding.ASCII.GetBytes(_jwtSettings.SECRET);
var currentTime = DateTime.Now;
var tokenDescriptor = new SecurityTokenDescriptor
{
Expires = DateTime.Now.AddMinutes(2),
SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
};
var token = tokenHandler.CreateToken(tokenDescriptor);
var tokenString = tokenHandler.WriteToken(token);
rs.Token = tokenString;
Auth filter to validate token:
public void OnAuthorization(AuthorizationFilterContext filterContext)
{
if (!ValidateToken(filterContext.HttpContext.Request.Headers["TOKEN"]))
{
filterContext.Result = new UnauthorizedResult();
}
}
private bool ValidateToken(string authToken)
{
try
{
var tokenHandler = new JwtSecurityTokenHandler();
var validationParameters = GetValidationParameters();
SecurityToken validatedToken;
IPrincipal principal = tokenHandler.ValidateToken(authToken, validationParameters, out validatedToken);
return true;
}
catch(Exception ex)
{
return false;
}
}
private TokenValidationParameters GetValidationParameters()
{
return new TokenValidationParameters()
{
ValidateLifetime = false, // Because there is expiration in the generated token
ValidateAudience = false, // Because there is no audiance in the generated token
ValidateIssuer = false, // Because there is no issuer in the generated token
//ValidIssuer = _appSettings.ValidIssuer,
//ValidAudience = _appSettings.ValidAudience,
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secretkey)) // The same key as the one that generate the token
};
}
What can be the issue?