<label for="userEmail">User Email:</label><br />
          <input type="email" class="userMobile" id="userEmail" name="userEmail"
            [(ngModel)]="selectedLocker.lockeruseremail" required pattern="[a-z0-9._%+-]+@[a-z0-9.-]+.(com|in)$"/><br />

The pattern requires the email to be in the format [email protected] or [email protected], but it still allows submission without .com or .in.