Laravel不保存数据库中的文本区域值

我真的无法弄清楚为什么这段代码不保存文本区域值出了什么问题。除了保存文本区域内容外，所有其他事情都工作正常。如果我删除文本区代码，它会成功保存。

这是控制器操作：

public function store(CompanyRequest $companyRequest)
    {
       $company = new Company;
       if($companyRequest->isMethod('post')){
       $company->companyname    = $companyRequest->companyname;
       $company->companydescription    = $companyRequest->companydescription;
       $company->save();
       return redirect()->route('companyindex')->with('message', 'Your question has been posted.');
       }else{
            return redirect('company-create')->withErrors($companyRequest)->withInput();
        }
    }

这是边栏选项卡视图：

{!! Form::textarea('companydescription', Input::old('companydescription'), ['class'=>'mid first-input-div', 'id'=>'companydescription']) !!}

这是请求文件;

class CompanyRequest extends Request
{
    public function authorize()
    {
        return true;
    }
    public function rules()
    {
        return [
                'companyname'           => 'required|min:5|max:300',
                'companydescription'    => 'required|min:200|max:250'
            ];
    }