SMART IPTV APP ISSUE

Is it a Play Store message, or a message that looks more dark/Android like?
Might be worth trying to find an APK to attempt an install manually. https://www.apkmirror.com/ , http://www.aptoide.com/ and https://apkpure.com/ are a few places to search. I can't vouch for its authenticity or it being virus free, but https://apkpure.com/smart-iptv/eu.siptv.video looks to be the one you need, if you were attempting to install https://play.google.com/store/apps/details?id=eu.siptv.video . If you're searching for APKs, taking the ID part from the Play Store URL (eu.siptv.video in this case) can be a good search term.

Please note that you may find someone has uploaded an infected application to these sites, so it is worth running a scan after installing something from them (see https://droidbox.co.uk/how-to/antivirus-malware-protection-for-android-devices/ ).
If you want to keep as safe as possible, only download applications from the Play Store or the DroidBOX Market.

 

(Don't know if it is in the DroidBOX Market, that was just a general warning for obtaining any applications outside of the normal safe locations.)