Trouble using a list as checkbox input in form

[ElTacitos]

I'm trying to use a list of string as value for checkbox in a form() but I all I can get is the last object I selected.
Here is what I currently have:

const numbers = [1,2,3]
const formValues = await form(`
  numbers.map((num) => `
    <div>
      <input type="checkbox" id="${num}" name="selectedNums" value="${num}"\>
      <label for="${num}">${num}</label>
    </div>
  `).join("\n");
  <button type="submit">Submit</button>
`)

If I check 1 & 2 and then inspect formValues all I get is:

{
    "selectedNums": "2"
}

Am I doing something wrong ?