====/igg/greenfeecards====
Golfers can have bought cards to play multiple rounds of golf. Usually the rounds are deducted from the balance per course loop (18 holes = 2, 9 holes = 1). But it is also possible to just reduce the balance with 1 regardless of the number of holes.

You can retrieve any cards they have bought and their balance with this interface. The result is given as a formatted string and as an ablsolute number.

parameters:
|auth	|the authorisation code you received from Intogolf BV (mandatory)|
|relnr	|client id of the use (mandatory)|
|relkey	|the hash key that was provided upon login (mandatory if relnr>0)|

example: https://backend.ikgagolfen.nl/igg/golferregistrations?auth=<your authorisation code>&relnr=686095

result:
<code>{
  "greenfeecards": [
    {
      "grfnr": 703,
      "grfname": "midweek 75 x 18 holes",
      "balancestr": "47x18h. + 1x9h.",
      "balancenum": 95
    }
  ]
}</code>

if a wrong authorisation code is provided, the backend will return “no authorisation”