Help! I am unable to remove system apps.

Try Titanium Backup. Last time I rooted a phone that could remove system apps.

 

System apps may be baked into the OS and UI itself and therefore may not be able to be uninstalled.

 

are you sure you are rooted? was magisk installed correctly? do you have a custom recovery as well?

 

I don't know. HTC had a secondary security flag (S-On/S-Off) that would prevent granting RW access to /system when Android was running, but I hadn't heard of such a thing with Samsung. Of course Samsung build a lot of security stuff in (e.g. their Knox system) so it's far from impossible - I'm afraid I've never tried modifying a recent Samsung, so can't say.

Maybe try from recovery mode. I assume you have a custom recovery, and most of those have an ADB daemon, so you should be able to run ADB with the phone in recovery mode. Then see whether you can use ADB to uninstall the apps. You should have write access in recovery mode because otherwise the recovery would not be able to flash anything.

Warning: take a nandroid backup (backup made using recovery) before removing anything. If you get it wrong and remove something that's more important than you think it is you may find that the phone won't boot. Less severe problems can also arise if there is a dependency between specific apps (e.g. if there is one part of app A which links to app B then removing B can cause A to crash when that function is opened - I have seen this first-hand). You probably know all this, but you'd be surprised how many people we've had here over the years asking for help because they removed something that they didn't think they used and now the phone won't work at all, so I'm posting the warning to be safe.

 

The app says it cannot gain R/W permissions, which implies that it requested them but could not get them. I assume you have granted root permissions to that app, in which case it suggests that the request could not be granted. I'd check its settings just in case there's something there to mount system R/W (I vaguely remember there being something in Titanium, but it's been years since I used that so can't be certain), but if it is that the app is asking and the system can't or won't grant it there may not be much more you can do from within android itself.

As I noted above, it might be worth trying ADB in recovery mode, since you definitely can write to /system in that mode. Heck, you could try using ADB when running Android - but if you do, reboot the phone afterwards to see whether it worked (if you can't modify the system it might still appear to uninstall but would "return" after a reboot).

Otherwise, for that particular app why not just disable it? It's not as if you'll gain any real space by uninstalling it (the system partition won't shrink, and that's where most of the app will be), and once disabled it can't run, update or anything else. I can see the point of uninstalling apps which the system won't let you disable (with due care that nothing depends on them), but there's very little gain from uninstalling if you can disable (apart from some personal satisfaction). And of course you should follow the first rule of root club: take a nandroid before making any change to the system software, including uninstalling system apps.

 

Although system level apps on Android cannot be removed from the device. Android does allow you to disable those apps.
Some apps are granted Android administrator access. These will prevent you from uninstalling them unless you revoke their administrator privilege. Sometimes, malware can also use administrator privilege to wreak havoc on your phone.

 

But Android doesn't allow you to disable all system apps. In some cases that is for a good reason, but some manufacturers (and carriers) abuse that to prevent you disabling stuff that has no effect on anything else (in some cases stuff they have been paid to pre-install). The latter is an annoyance, but the only things you can do about that are either root the phone or buy from a manufacturer who doesn't do that.