Creating an item & then populating it with data

Hi all,

I’m trying to create items on my own board using garphql, axios and nodejs.

for some reason when i try to send the columnValues i get the followong errMessage:

 errors: [
    {
      message: 'Variable columnValues of type JSON! was provided invalid value',
      locations: [Array],
      value: null,
      problems: [Array]
    }
  ],

and here is what i’m doing 🙂

 const createItem = {
          query: `
          mutation ($boardId: Int!, $groupId: String!, $itemName: String!) {
            create_item (
              board_id: $boardId,
              group_id: $groupId,
              item_name: $itemName,
            ) {
              id
              }
            }`,
            
            variables: {
              boardId: +BOARD,
              groupId: "topics",
              itemName: `${title}`,
              }
            }

            axios.post(`${URL}`, createItem, {
                headers: {
                  Authorization: `${KEY}`
                }
              }).then(res => {
                console.log(res.data.data.create_item.id)
                let itemId = res.data.data.create_item.id;

              const fillItem = {
                query: `
                mutation ($boardId: Int!, $itemId: Int!, $columnValues: JSON!) {
                  change_multiple_column_values (
                    board_id: $boardId,
                    item_id: $itemId,
                    column_values: $columnValues
                  ) {
                    id
                  }
                }`,

                variables: {
                  boardId: +BOARD,
                  itemId: +itemId,
                  groupId: "topics", 
                  columnValues: JSON.stringify({
                    text8: problem_type,
                    text9: problem_sub_type,
                    text7: third_level_category,
                    text5: description, 
                    text4: assigned_group,
                    text1: responsability,
                    text6: request_user,
                    text61: submit_user,
                    text97: request_user_email,
                    text3: request_user_cellphone,
                    text33: module_klh,
                    text50: df_phone_number,
                 
                  })
                }
              }
              axios.post(`${URL}`, fillItem, {
                headers: {
                  Authorization: `${KEY}`
                }
              }).then(res => console.log(res.data.errors[0]))
              .catch(err => console.log(err.data))