I just figured this out, at least for me. After Pie update my wifi setting got changed to metered instead of original setting unmetered. (Metered means it will stop your data once it gets to set limit) This cause the wifi to continuously jump on and off all the time... You have to go into your wifi and click on your network and go to advanced. Make sure tab on bottom is set to "Treat as unmetered network" and click save... Boom.... No drop. Hope this helps...did it to me on my note 8 and 9...think it was more Samsung issue than Android. But this works... 👍👍👍
Same issue, same phone. Google Fi is the carrier (actually via TMobile). It's particularly annonying since Google charges me for any data I use. The same thing is also happening on my wife's S10+ as well.
I am getting a replacement phone next week from my carrier. Samsung and Tmobile could not fix the issue. The phone is still under warranty. The phone is being delivered to the store and I will go there to turn in the current phone I have with the issues. I will not be transferring settings from current phone to the new phone. My files are all stored on my SD card and backed up in the cloud. Just will have to go through the pain of setting up all my email accounts and various other apps for travel and work. Hopefully the new phone will be void of bugs.