There are several factors that may cause the app to stop working. In situations like these, you should always have a Backup of your wallet.
Here are some things you can do to try and fix this issue:
Step 1: Restart your Device
Step 2: Checking your Connection
In order for the app to work, you need to be online. Try opening a Browser or opening another app that connects to the internet. Switch off/on your Mobile Data, try to reconnect to a different WiFi Hotspot.
Step 3: VPN Usage
In some cases, your connection gets blocked when you are on a country that prevents accessing Crypto related sites or app.
Step 4: Update Your Device OS
Newer versions of Maiar app requires that you also have the latest OS on your device. For iOS, you need at least iOS 13 and higher. For Android devices, Android OS 7.0 or higher is required.
Step 5: Install Latest App Version
Always check for the most recent version available for your device and Download Maiar only from official sources.