(REQ) Xerochat Template Mega Pack (chatpion)

Hello.. nrw here.
I got a problem. How to fix this err msg:

A PHP Error was encountered​

Severity: Warning
Message: foreach() argument must be of type array|object, int given
Filename: database/DB_query_builder.php
Line Number: 1132


The said part:
/**
* GROUP BY
*
* @param string $by
* @param bool $escape
* @return CI_DB_query_builder
*/
public function group_by($by, $escape = NULL)
{
is_bool($escape) OR $escape = $this->_protect_identifiers;

if (is_string($by))
{
$by = ($escape === TRUE)
? explode(',', $by)
: array($by);
}

foreach ($by as $val)
{
$val = trim($val);

if ($val !== '')
{
$val = array('field' => $val, 'escape' => $escape);

$this->qb_groupby[] = $val;
if ($this->qb_caching === TRUE)
{
$this->qb_cache_groupby[] = $val;
$this->qb_cache_exists[] = 'groupby';
}
}
}

return $this;
}



I'm using a v8.1.4. Trying out the script. Everything works but this err msg pop up.
Line 1132: foreach ($by as $val)

Plz advice me on this. I'm using a script originated from here but I can't find the one who posted it to ask for his/her advice. Thanks in advance