In order to make sure the SDK uses the iOS keyboard only, and not third party ones, disable app extensions for keyboard as follows:

In your AppDelegate, add the method application(_:shouldAllowExtensionPointIdentifier:) with the implementation of:

func application(_ application: UIApplication, shouldAllowExtensionPointIdentifier extensionPointIdentifier: UIApplicationExtensionPointIdentifier) -> Bool {
    return extensionPointIdentifier != UIApplicationExtensionPointIdentifier.keyboard
 }