Duplicate upload form submission - JS with Formdata

Question

Come on, you guys! I have a problem with Formdata to send files via AJAX using Formdata. I made an image registration that after loading an image, the user can load a second image. However, loading the page, when registering the first image, everything goes well, in the second image, it is sent 2 times, in the third image, 3 times and so on. When you refresh the page, you restart the cycle. I gave as an example this form, but this happens with all the forms I send with this method. It is as if at each sending click, the DOM was duplicated and each "copy" performed the same tasks. I tested it on other browsers, same thing.

Follow the code below.

HTML

<form id="form_banner" method="post" enctype="multipart/form-data">
    <div class="row" id="conteudo">
        <div class="col s12 input-field">
            <div class="config_img_g">
                <div class="arquivo_midia">Novo banner <span>(Formatos jpg ou png com até 2Mb de tamanho)</span>    </div>
                <input type="file" name="banner" accept=".png, .jpg, .jpeg" class="dropify fileSize">
            </div>
        </div>                  
        <div class="col s12 m3">
            <button id="banner_salvar" class="btn btn_l confirma">Cadastrar</button>
        </div>
    </div>
</form>

JS

function banner_Salva(){
    $('#form_banner').submit(function(e){
        e.preventDefault();
        let formData = new FormData(this);
        if($('.dropify-render').html()!=""){ //Se houver alguma imagem, esse objeto é preenchido com uma imagem. Verificação apenas para não enviar o campo vazio.
            $.ajax({
                type:           "POST",
                url:            "https://"+dominio+"/banner-salva",
                cache:          false,
                contentType:    false,
                processData:    false,
                data:           formData,

                beforeSend:function(){
                    $("#modal").html("<h6 class=\"modal_tit\">Guardando as informações...</h6><div class=\"progress\"><div class=\"indeterminate\"></div></div>")
                    $("#modal").modal("open")
                },

                success: function(retorno){
                    if(retorno.trim() != "OK"){
                        $("#modal").modal("close"),
                        Swal.fire({
                            title:  "Ops!",
                            html:   retorno,
                            icon:   "error",
                            confirmButtonText: "OK"
                        })
                    }
                    
                    $("#modal").modal("close")
                    //As próximas linhas tratam a ferramenta dropfy para deixá-lo pronto (limpo/vazio)
                    $(".dropify-preview")           .removeAttr("style", "display-block")
                    $(".dropify-preview")           .attr("style", "none")
                    $(".dropify-render")            .html("")
                    $(".dropify-filename-inner")    .html("")                           
                }       
            })
            
        }else{
            Swal.fire({
                title:  "Ops!",
                html:   "O banner precisa de uma imagem para ser carregado!",
                icon:   "error",
                confirmButtonText: "OK"
            })
        }

    });
}