AR Foundation: Adding image to MutableRuntimeReferenceLibrary returns the status "ErrorUnknown"

Hi! I'm trying to add images to the tracked image manager in runtime, using the following code:

 void AddImage(Texture2D imageToAdd)
 {
     if (m_TrackedImageManager.referenceLibrary is MutableRuntimeReferenceImageLibrary mutableLibrary)
     {
 
         //Used in case the image is in a TextureFormat not supported by the image library
         if (imageToAdd.format != TextureFormat.RGBA32)
         {
             Debug.Log("Different format");
             imageToAdd = ChangeFormat(imageToAdd, TextureFormat.RGBA32);
         }
 
         //Add the image to the library
         var addImageJob = mutableLibrary.ScheduleAddImageWithValidationJob(
             imageToAdd,
             "john",
             0.3f);
 
         //Wait for the add image job to end while debugging its status
         while (!addImageJob.jobHandle.IsCompleted)
         {
             Debug.Log("Adding images");
             Debug.Log("Status: " + addImageJob.status);
         }
 
         Debug.Log("Status: " + addImageJob.status);
 
         Debug.Log("Library Count: " + mutableLibrary.count);
 
     }
 }

In the process of adding the image, the status is logged as "None" several times, but eventually it becomes "Error Unknown".

I have tested this with different images, with different TextureFormats and both jpg's and png's, and they all return the same result.

I also thought that it could happen because the image had insufficient features. However, I also tried with the example marker in ARCore page and even used their arcoreimg tool to check the quality score of the images I used.

Do you know what can be the cause of this error? I know it says the error is unknown, but it probably has a solution :).

Thanks!