There might be some additional CSS hampering your bootstrap classes, as the contents are at center. Look below
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet"/>
<div class="row justify-content-center">
<form action="" method="POST">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control" value="Enter your name">
</div>
<div class="form-group">
<label>Location</label>
<input type="text" name="location" class="form-control" value="Enter your location">
</div>
<div class="form-group">
<button type="submit" name="save">Save</button>
</div>
</form>
</div>
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