Internet connection problem in iOS version : 11.2.1 – Bangla Newspaper - Prothom Alo Review

When I open the app, it always brings a pop up saying “check your internet connection” although my internet both WiFi and cellular are on. I tried turning WiFi off and running on cellular only- same result. However, the app is able to send push notifications regardless. App used to work on previous version of iOS. Device : iPhone 7 iOS version : 11.3
Review by RAJU NyC iPhone 6+ on Bangla Newspaper - Prothom Alo.