This error is usually caused when an object is trying to be used by a script but does not refer to an instance of an object. Unity has a help article on this here, can you please check your code to see if this solution can help?  https://support.unity.com/hc/en-us/articles/206369473-NullReferenceException

@Haley Pace If you look at the stack trace you can see that everything is in the RevenueCat SDK.  In fact, I am calling PurchasePackage() on an object that was given to me by the GetOfferings() call.  

I know what a Null reference is, and I am not passing a null reference.  Here is my code:

      if ( package == null ) {
        return;
      }

      Debug.Log( "Package: "+ package );

      Purchases.PurchasePackage(package, (identifier, info, cancelled, error) => {

It seems to me that something in the RevenueCat SDK is attempting to serialize to JSON for the API call for the purchase, and a field somewhere in the Package object tree is null.  Is there some configuration in RevenueCat somewhere that is missing that causes a null value?  I may be able to fix that if someone would just tell me what it is … but regardless, the SDK should handle it.

I don’t want to post the contents of the Debug.Log() output here, but package is definitely not null.

 

@Haley Pace @Tavis Elliott  In my case after debugging I found out that TargetingContext.RuleId was null which resulted in above error.
So I changed this condition in PresentedOfferingContext.ToJsonString() method

if (TargetingContext != null)

to this

if (TargetingContext != null && !string.IsNullOrEmpty(TargetingContext.RuleId))

Now it works.

@Kaushik Ah, thanks for the insight!  I’m loathe to copy and modify an external SDK, but if that’s what I have to do for now …  I took a different approach, and made these modifications:

In JSONString#WriteToStringBuilder() I changed this:

            aSB.Append('\"').Append(Escape(m_Data)).Append('\"');

To this:

          if ( null == m_Data ) {
            aSB.Append("null");
          }
          else {
            aSB.Append('\"').Append(Escape(m_Data)).Append('\"');
          }

I made similar changes in JSONObject#WriteToStringBuilder() to check for null key/value in the Dictionary, though I don’t think that was my problem.

@Haley Pace Any thoughts about how soon I can get a fix for this issue in the official SDK?  Conversely, is there a configuration somewhere in RevenueCat or my Google play store setup that I can change to cause the “ruleId” to not be null?