I recently bought a Samsung Galaxy S10e and when I'm using some apps, currently WhatsApp and Skype, I receive a notification from "Android System" saying that particular app cannot connect to the wifi the phone is connected and if that app can use mobile data instead.
I had a Galaxy S8+ before with Android Oreo and never had this problem. To be clear, my problem is not that the phone can't connect to the wifi. The phone connects without problem and I can access the internet on chrome or the samsung browser. It's just some specific applications that apparently can't connect to the wifi.
ps. this post is tagged as "samsung-galaxy-s10" because I couldn't create the tag for "samsung-galaxy-s10e"