diff --git a/templates/register.htm b/templates/register.htm
index 3030101..200d46c 100644
--- a/templates/register.htm
+++ b/templates/register.htm
@@ -463,8 +463,8 @@
 
     <div class="form-outline col-md-5">
         <label class="form-label fw-bold" for="paper_id">Paper ID</label>
-        <input type="text" class="form-control fs-4" name="accepted_paper_id" id="paper_id" <?php echo isset($_POST[ 'author']) ? 'placeholder="0"' : 'disabled' ?> value="
-        <?php echo isset($_POST['paper_id']) ? htmlspecialchars($_POST['paper_id']) : '' ?>" />
+        <input type="text" class="form-control fs-4" name="accepted_paper_id" id="paper_id" <?php echo isset($_POST[ 'author']) ? 'placeholder="0" required' : 'disabled' ?>
+        <?php echo isset($_POST['accepted_paper_id']) ? 'value="'.htmlspecialchars($_POST['accepted_paper_id']) . '"' : '' ?> />
         <div class="invalid-feedback">
             Please provide the ID number of your accepted paper.
         </div>