openssl_decrypt(): IV passed is 29 bytes long which is longer than the 16 expected by selected cipher, truncating

I get the error message on the title when I try to login to some accounts from the admin side.This is the code:

private function decryptString($string){    $ciphering = "AES-128-CTR";      $options = 0;     $decryption_iv = '4F109F987HJ91597CCB4AF4D6';     $decryption_key = "(Ct:>)xByg68>In&l1P!;6dhd>llD-zel.9aSC+986cn;j8,.J";     $decryption = openssl_decrypt($string, $ciphering,                 $decryption_key, $options, $decryption_iv);     return $decryption;}

the log says the error is in the "$decryption = openssl_decrypt" line

tried changing to 256-ctr but it does not do anything. Cant think of anything else and changing the aes mode is not an option.