Subscribe issue

Hello,
Hope this finds you well,

I followed your documentation on subscribe widget and after creating mailchimp account, I tested the widget in various Canvas pages and it works fine (see attached picture), except one subscription widget located in ( blog-both-sidebar.html) as below. this one does not work.
Note: the action attribute originally was having # sign, but I replaced it to have the (include/subscribe.php)
The form did not have ( method="post" ) and I included it (try both with and without) ...…But at the end, It didn't work.

SUBSCRIBE WIDGET CODE:

					  			<div class="widget subscribe-widget clearfix">

								<h4>Subscribe to Biomedresearches Newsletter</h4>
								<h5>Subscribe to Our Newsletter to get Important News, Articles & More:</h5>
								<form action="../include/subscribe.php" method="post" class="my-0">
									<div class="input-group mx-auto">
										<input type="text" class="form-control" placeholder="Enter your Email" required="">
										<div class="input-group-append">
											<button class="btn btn-success" type="submit"><i class="icon-email2"></i></button>
										</div>
									</div>
								</form>
							</div>

Kindly advise
Note: in the include folder, there are three subscribe.phb files (subscribe-cm ; subscribe-email ; subscribe), so, Am I using the wrong file (knowing the subscribe.php) file worked well with the widget in the attached picture.

Regards