500 internal server error while creating item with column_values

I am using Postman as well as ruby platform to create a new item with populated columns, however I am able to create an Item with item_name, but when I am adding other columns value, api returning 500 internal server error. I don’t know what is going wrong here. I tried interpolating my variables in different ways but nothing worked. So, reaching out to this forum. If anybody can help in this.

Below is my request payload from postman which is working absolutely fine.

{
“query”: “mutation { create_item (board_id: xxxxxx, group_id: sample, item_name: newItem) {id} }”
}

Below is my request payload from postman which is not working.
{
“query”: “mutation { create_item (board_id: 1472475168, group_id: topics, item_name: newItem, column_values: {“text”: “noissue”}) {id} }”
}

It is giving me parsing error:
{
“errors”: [
{
“message”: “Parse error on “text” (STRING) at [1, 101]”,
“locations”: [
{
“line”: 1,
“column”: 101
}
]
}
],
“account_id”: xxxx
}

I tried this as well. But it is giving 500 internal server error.
{
“query”: “mutation { create_item (board_id: 1472475168, group_id: topics, item_name: newItem, column_values: {text: “value”}) {id} }”
}

@Ayelet Can you help in this?