private async Task RefreshAccessToken(bool allowCachedToken = true)
{
var token = string.Empty;
if (allowCachedToken)
{
token = _authorizationHandler.RetrieveLocalAccessToken();
}
if (string.IsNullOrEmpty(token))
{
token = await _authorizationHandler.RetrieveRemoteAccessTokenAsync();
}
_httpHandler.UseBearerToken(token);
}