Hello Nayem,
I finally fix this issue. I change

/plugins/dokan/assets/css/dokan-extra.css

#wrapper {
	/*width: 960px;*/
	width: 0 auto;
	margin: 0 auto;
	margin-top: 0 auto;

It works!!! 🙂

Hello,

I am very glad to know that. I am marking this topic as resolved.

Thanks.