Problem with logo

Hello, its my first time that i am using Coming Soon Page, Under Construction & Maintenance Mode by SeedProd plugin and i have a problem with logo. In Settings-> Content-> Page Settings->Logo when i upload my logo it doesnt show. I have tried both jpeg and png images in almost all the sizes. The same happen even if i put it from Message->Add Media. Why is this happened?

ps. Background image upload it ok!