object reference is required but only inside a switch

When i try to run my program i get an "An object reference is required for the non-static field, method, or property 'MonoBehaviour.StartCoroutine(IEnumerator)'" error

Code (CSharp):

1. public static void DayEvent()
2.     {
3.         rand = Random.Range(1, 10);
4.         switch (rand)
5.         {
6.             default:
7.                 StartCoroutine(BuyFood()); //Error on this line
8.                 break;
9.         }
10.     }

but BuyFood is definitely static:

Code (CSharp):

1. public static IEnumerator BuyFood()
2.     {
3.         answered = false;
4.         question = "Would you like to buy food?";
5.         PlayerManager.answer = 0;
6.         TextManager.ChangeText(question);
7.         yield return new WaitUntil(() => answered == true);
8.         Debug.Log("waitover");
9.         if (PlayerManager.answer == 1)
10.         {
11.             if (PlayerCharacter.player.Gold > 5)
12.             {
13.                 PlayerCharacter.player.Hunger = +1;
14.                 PlayerCharacter.player.Gold -= 5;
15.                 TextManager.ChangeText("You bought food");
16.                 PlayerManager.answer = 0;
17.             }
18.             else
19.             {
20.                 TextManager.ChangeText("You do not have enough money");
21.                 PlayerManager.answer = 0;
22.             }
23.         }
24.         else if (PlayerManager.answer == -1)
25.         {
26.             TextManager.ChangeText("You didn't buy food");
27.             PlayerManager.answer = 0;
28.         }
29.         yield return new WaitForSeconds(5);
30.         TextManager.ChangeText("");
31.     }

ive been able to run this before by calling it like that before, its just when i moved it into a switch it stopped working, any suggestions?

 

It's because DayEvent is static and you can't start a coroutine from a static function. There's some discussion and workarounds here: https://forum.unity.com/threads/c-coroutines-in-static-functions.134546/