slider on details page PLEASE Help

That will only be possible with some CSS and we would need to see the page for that, so we would need a URL. The simplest would be to narrow the column width for the detail page.
But it will never work if you allow users to upload images, it will only work if you control all images your self and they are all 100% the same size.

I can see the page now, but there is no point changing it unless you will use only images of exactly the same size, which you are not.

Add this CSS

.geodir_flexslider .geodir-slides img {
    width: 770px;
}

You’re welcome 🙂