Hi
From looking the information that you have provided, I would ensure that you have an entry for both of these:
[OnlineSubsystemGooglePlay.Store]
IsAllowedToMakePurchases=True
[/Script/AndroidRuntimeSettings.AndroidRuntimeSettings]
bEnableGooglePlaySupport=True
in your config file. On the topic of IOS, you will need to add the OSSIOS to your *.build.cs file:
DynamicallyLoadedModuleNames.Add("OnlineSubsystemIOS");
I hope this is useful.
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