Simple if statement not working

programming
1

$variable = $_POST[‘variable’];
if ($variable == “certaintext”) {
do something;
} else {
do something else;
}

everything else outside this script is working fine, but here it’s ignoring the if statement and doing both of what is inside the if and the else statements. the $variable works fine if i echo it, so i don’t know what’s wrong with this.

thanks in advance for any help.