Acrobat Reader DC is free. You purchased something else so let's start with the product name. Adobe have such a number of products, it's hard to keep track.
Then, what exactly happens when you try to edit. Text, anyway, adding a logo may be ambitious.
I purchased Acrobat Pro Dc Subscription( month-to-month) version. When I try to edit any part of the file like text or the logo part, it just doesn't allow me. When I go to the right hand part of the screen and click on edit it only give me the option to learn more and when I click on that it takes me to another window where I have to purchase the editing tool. This version of Acrobat should have he edit tool included, at least that's what the advertisement said before I purchased it.
You're still using Reader. Acrobat is a different application entirely.
You need to download, install and then use it to have access to the editing functions you want.