[ISSUE] com.njj.mactivepro (MActivePro) circumvents Afwall blocking

[enolp]

Describe the bug
com.njj.mactivepro (MActivePro) app circunvents Afwall blocking when all interface checkboxes are activated and "Block selected" option is enabled. Afwall does not detect any activity from app and shows "0 B" values for upload/download

Firewall Logs
Impossible to get any log because Afwall detects nothing from this Chinese app which is very very strange.

Smartphone (please complete the following information):

• Device: Samsung A71
• Android OS: LineageOS 21

Additional context
This is an shitty app (obtainable on Google Play and very bad translated) from some obscure Chinese vendor which is required to use these cheap smartwatches. Biometric data can be sent to an untrusted Chinese server, so I use Afwall to avoid this behavior but it is useless. In fact, this app circumvents Pi-Hole (blocking its Chinese domains does nothing because the app is able to download content from internet). However, if "Any app" item has all interface checkboxes activated on Afwall, MActivePro is unable to reach internet.

If someone wants to debug this issue because I don't know how to do it, you can download com.njj.mactivepro app from Play Store. NO smartwatch is required.

EDIT 1

After using "Visitors log in" from app, the server bans you during an unknown time.

[TheRealC0unt]

Why do you use the blacklist mode? It is the cleaner and more secure approach to use the whitelist mode anyway.
Per default, any app isn't allowed to connect anywhere outside, unless you whitelist it. This way, those shitty apps don't stand a chance.

Pihole is circumvented obviously by either a hardcoded DNS or simply by directly using an IP list, to avoid DNS lookups.

General advice: if an app uses these techniques, there are STRONG indications that there's shady stuff going on. Avoid using this shit completely.