There have been many complaints in the Forum about Contour failing with Amazon Prime, HBO Max, Disney and Paramount.
If you want to steam, I would suggest purchasing a device engineered to stream. Devices engineered to stream have better chipsets, operating systems and customer support. Adding streaming apps to a cable-box was just an afterthought to keep subscribers from cutting-the-cord.
My Roku must be 10 years old and I've never had a problem streaming with it, and there are plenty of contributors to attest they've never had problems with their choice of device, such as Chromecast, Fire TV Stick, TiVo. I understand having one box, one remote and voice command is convenient...but the platform is unreliable. Techs are even coming to your house and can't fix it.
Why can't you install/uninstall apps on your Philips TV? After a quick web search, I found plenty of how-to articles. Is your Philips connected to the Internet?
It just isn't an option. I've seen those how-tos as well, but they don't apply to my particular TV. I go into settings, and there is no option to manipulate the existing apps that are available to me. The apps just have randomly become available over the years. When I first got the set, there was no Hulu or Disney+ app on the screen when I would press Contour on the remote, then navigate to the Apps. Then one day, those two were suddenly available. The remote that came with my TV has buttons for Netflix, Vudu and Youtube, so my guess is it's an agreement between Philips and streaming providers on what apps are available and when. I don't know, I find it odd but it is what it is.
I don't understand if we're talking about the TV and you reference pressing the Contour button. The TV has its own operating system and apps and Contour has its operating system and apps. Two different platforms. The Contour box wouldn't have anything to do with steaming an app on the TV set. You'll need to use the TV remote to navigate the TV apps.
When I use the remote for the TV and go to it's apps, there is only a limited selection, and none of them are the ones I subscribe to. My TV is hooked up to the Contour box so that I can access Cox Cable. I have HBOMax and Netflix through Cox, but I also have Hulu, Disney+, and Prime Video and can access them with the Cox remote. I know it doesn't make sense, but I've spent countless hours looking for a way to manipulate the apps on my TV and it can't be done. It came with something called Net TV where the apps are found, and it just has a bunch of weird ones like Field and Stream, Popular Science, iFoodTV, Outdoor Life. Right now, NONE of my apps are working, so I will have to waste time exchanging this stupid Contour Box.