mysqli_select_db ожидает 2 параметра
//do the correction as below:
$conn = mysqli_connect('localhost', 'root', '');
//the first thing that you have to pass connection variable in the select_db as first parameter. as below.
mysqli_select_db($conn,'altislife-dev');
//also you have to pass connection variable in mysqli_query() as first parameter as given below.
$records=mysqli_query($conn,$sql);
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