Laravel-excel: entries!F347 -> Formula Error: Unexpected operator '='

[woogygun]

Im getting the following error, been struggling on this quite a bit.

entries!F347 -> Formula Error: Unexpected operator '='

public function exportCampaign(Campaign $campaign)
    {
        $entries = Entry::whereCampaignId($campaign->id)->get()->toArray();
        $campaign = $campaign->toArray();

        Excel::create('Filename', function($excel) use ($campaign, $entries) {

            $excel->sheet('campaign', function($sheet) use ($campaign) {

                $sheet->fromArray($campaign);

            });

            $excel->sheet('entries', function($sheet) use ($entries) {

                $sheet->fromArray($entries);

            });

        })->export('excel');
    }

[woogygun]

Ok i got this sorted. Turns out a user had filled out a '=' in one of the rows causing it to fall over.