กด submit form ไม่ทำงานใดๆ ไม่เปลี่ยนหน้า ไม่แจ้งเตือน แก้อย่างไรดี

<form action="article_save.php" enctype="multipart/form-data" method="post">
                           <center><div id="sho" style="display: none;"><img id="blah" src="#" class="img-thumbnail" width="300px" style="display: none;"><br><br></div></center>
                            <table class="table"> 
                              <tr>
                                <td width="20%"><h5>รูปภาพบทความ</h5></td>
                                <td width="30%">
                                    <input type="file" class="filestyle" name="ImageFile" id="ImageFile" data-buttonBefore="true" onChange="readURL(this);" accept="image/*" required> 
                                </td>
                                <td width="50%"></td>   
                                </tr> 
                               <tr>
                                <td width="20%"><h5>วันที่</h5></td>
                                <td width="30%">
                                <? date_default_timezone_set('Asia/Bangkok'); ?>                                
                                	<div class="form-group">
                                        <div class="form-line">
                                            <input type="text" class="datepicker form-control" value="<?= date('l d F Y'); ?>" name="date" required>
                                        </div>
                                    </div>
                                </td>
                                <td width="50%"></td>
                                </tr>                             
                                <tr>
                                <td width="20%"><h5>หมวดหมู่</h5></td>
                                <td width="30%">
                                <select id="select_mail" class="form-control show-tick" name="type" required>
                                        <option value="">-- เลือกหมวดหมู่ --</option>
                                        <option value="สุขภาพ">สุขภาพ</option>
                                        <option value="ความงาม">ความงาม</option>
                                        <option value="ผลิตภัณฑ์">ผลิตภัณฑ์</option>                                 
                                </select>
                                </td>
                                <td width="50%"><h5><span class="label bg-red">* จำเป็น</span></h5></td>
                                </tr>
                                <tr>
                                <td width="20%"><h5>เรื่อง</h5></td>
                                <td width="30%">
                                	<div class="form-group">
                                        <div class="form-line">
                                            <input type="text" class="form-control" placeholder="เรื่อง" name="head" required/>
                                        </div>
                                    </div>
                                </td>
                                <td width="50%"><h5><span class="label bg-red">* จำเป็น</span></h5></td>
                                </tr>
                                <tr>
                                <td width="20%"><h5>เนื้อหาบทความ</h5></td>
                                <td width="80%" colspan="2">
                                <div class="form-group">
                                	<div class="form-line">                                   	
                                    	<textarea id="ckart" name="ckart" rows="5" class="form-control" required></textarea>
                                <script>
			CKEDITOR.replace( 'ckart', {
				toolbar: [
					{ name: 'document', items: [ 'Source', '-', 'NewPage', 'Preview', '-', 'Templates', '-', 'Print' ] },	// Defines toolbar group with name (used to create voice label) and items in 3 subgroups.
					[ 'Cut', 'Copy', 'Paste', 'PasteText', 'PasteFromWord', 'Image' ],[ 'Table', 'HorizontalRule'],			// Defines toolbar group without name.
					'/',																					// Line break - next group will be placed in new line.
					{ name: 'basicstyles', items: [ 'Bold', 'Italic', 'Underline', 'Strike', 'Subscript', 'Superscript', 'NumberedList', 'BulletedList'] },
					[ 'JustifyLeft', 'JustifyCenter', 'JustifyRight', 'JustifyBlock', '-', 'Indent', 'Outdent'],
					[ 'Smiley', 'SpecialChar', 'Link', 'Unlink'],
					'/',
					[ 'Format', 'Styles', 'Font', 'FontSize', 'TextColor', 'BGColor']
				]
			});
								</script>
                                	</div>
                            	</div>                                
                                </td>
                                </tr>
                                <tr>
                                <td width="20%"><h5>จาก</h5></td>
                                <td width="30%">
                                	<div class="form-group">
                                        <div class="form-line">
                                            <input type="text" class="form-control" placeholder="แหล่งที่มา" name="from" required/>
                                        </div>
                                    </div>
                                </td>
                                <td width="50%"></td>
                                </tr> 
                                <tr>
                                <td width="20%"></td>
                                <td width="30%" align="center">
                                   <input type="hidden" name="sal" value="1">
                                    <button type="submit" class="btn bg-green">เพิ่มบทความใหม่</button> 
                                </td>
                                <td width="50%"></td>   
                                </tr>
                            </table>
                            	</form>