Could not load type 'System.IdentityModel.Tokens.TokenValidationParameters' 

Hi,
when i run it locally using vs 2017, i got this runtime error

Line 47:             app.UseCookieAuthentication(new CookieAuthenticationOptions()); Line 48:  Line 49:             app.UseOpenIdConnectAuthentication( Line 50:                 new OpenIdConnectAuthenticationOptions Line 51:                 {
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