check fragment state before displaying the next screen

Author: codeismail-waver

rave_android/src/main/java/com/flutterwave/raveandroid/ghmobilemoney/GhMobileMoneyFragment.java

@@ -232,8 +232,10 @@ public void showWebPage(String authenticationUrl
     ) {
 
 //        this.flwRef = flwRef;
-        new RaveVerificationUtils(this, ravePayInitializer.isStaging(), ravePayInitializer.getPublicKey(), ravePayInitializer.getTheme())
-                .showWebpageVerificationScreen(authenticationUrl);
+        if(isAdded()){
+            new RaveVerificationUtils(this, ravePayInitializer.isStaging(), ravePayInitializer.getPublicKey(), ravePayInitializer.getTheme())
+                    .showWebpageVerificationScreen(authenticationUrl);
+        }
     }