jQuery.when(
  jQuery.ajax({
    type: "POST",
    dataType: "json",
    url: "../custom_scripts/api/anmeldung/zum_turnier_anmelden_check.php",
    data: {
      turnier_id: turnier_id
    }
  }),
  jQuery.ajax(
    {
      url: "../custom_scripts/api/user/get_user_info.php",
      type: 'GET',
      dataType: 'json',
    }
  )
).then(function (resp1, resp2) {
  if ( resp1[0].check === 0 ) {
    
  }
});