Receive array from HTML form in FastAPI

I'm trying to submit a form through post in FastAPI and get a form variable that is stored as a list. When I read back the value all I get is an empty list. There are several variables that will eventually be in list form but all I am trying to get at the moment is the array that holds the quantity values.

What am I doing wrong?

Here is my code:

Python Code

@app.post("/edit_bom")
def edit_bom(board_id: int = Form(...), quantity: list = Form(...)):
    print("Editting BOM, board ID: " + str(board_id))
    print("quantity: ", quantity)
    
    return RedirectResponse(url=f"/get_bom_details/" + str(board_id), status_code=303)

HTML Code

<form method="post" action="/edit_bom" id="parent-form">

  <div class="mb-3 row">
    <div class="d-grid gap-2 col-2">
      <button type="button" class="btn btn-outline-primary add-one-more"><i class="fas fa-fw fa-plus-square"></i> New Row</button>
    </div>

    <div class="d-grid gap-2 col-2">
      <button type="submit" name="action" value="save-bom" class="btn btn-outline-success"><i class="fas fa-fw fa-check"></i> Save</button>
    </div>
  </div>

  <div class="mb-3 row" id="header">
    <label class="col-form-label col-sm-1 text-sm-end"></label>
    <div class="col-sm-7">
      <h3>Part Number</h3>
    </div>
    <div class="col-sm-2">
      <h3>Quantity</h3>
    </div>
    <div class="input-group col">
      <h3>Edit</h3>
    </div>
    <div class="input-group col">
      <h3>Delete</h3>
    </div>
  </div>
  <div class="mb-3 row bom-line-item copy-fields" id="entry">
    <label class="col-form-label col-sm-1 text-sm-end child-row-label">1</label>
    <div class="col-sm-7 child-outer">
      <input type="text" name="part-name_1" id="0" class="form-control child-part-name" placeholder="Board Number" value="ISL73847SEHDEMO1ZB">
    </div>
    <div class="col-sm-2 child-outer">
      <input type="number" name="quantity[]" id="0" class="form-control child-part-quantity" placeholder="Enter quantity" value="1">
    </div>
    <div class="input-group col child-outer">
      <button id="btn-edit_1" class="btn btn-primary child-btn-edit" type="button"><i class="fas fa-fw fa-edit"></i></button>
    </div>
    <div class="input-group col child-outer">
      <button id="btn-del_1" class="btn btn-danger child-btn-delete" type="button"><i class="fas fa-fw fa-ban"></i></button>
    </div>
  </div>
  
  <div class="end-of-list" name="noOfRows" value="1"></div>
  <input type="hidden" name="board_id" value="1">
</form>

My output in the command prompt:

Editting BOM, board ID: 1
quantity:  []