services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(JwtBearerDefaults.AuthenticationScheme, o => {
        o.TokenValidationParameters = new TokenValidationParameters()
        {
            ValidateLifetime = true,
            LifetimeValidator = (DateTime? notBefore, DateTime? expires, SecurityToken securityToken, TokenValidationParameters validationParameters) => {
                // --> my custom check <--
            }
        };
    });

services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(JwtBearerDefaults.AuthenticationScheme, o => {
        o.TokenValidationParameters = new TokenValidationParameters()
        {
            ValidateLifetime = true,
            LifetimeValidator = (DateTime? notBefore, DateTime? expires, SecurityToken securityToken, TokenValidationParameters validationParameters) => {
                Microsoft.IdentityModel.Tokens.Validators.ValidateLifetime(notBefore, expires, securityToken, validationParameters);
                // --> my custom check <--
            }
        };
    });