Unable to install apk file

[falkondor]

Hello experts, 🙂 

I'm unable to install an apk file. In past i was able to.. on clicking the file a system warning used to pop up and then it simply got installed.

Now however when I click on the apk file it opens up the Zoom app for some reason. When I uninstalled Zoom, the system said it could not be opened. 

Pls help how can I install an apk file. 

Thank you 

[falkondor]

I appreciate you responding here (after 15+ days).
I have been asking regarding getting a new battery for my Note9 through the route you are advising - no proper solution in 3 attempts over last 4 days. Hope you (and your functional head) understand the issues of Samsung customer support. Thx