"error": {
    "code": "internal_api_error_TypeError",
    "info": "[e6623aa8a06760b8d51986b2] Exception caught: Argument 1 passed to Wikibase\\Repo\\Merge\\Validator\\NoCrossReferencingStatements::validate() must be an instance of Wikibase\\DataModel\\Entity\\StatementListProvidingEntity, instance of Wikibase\\DataModel\\Entity\\Item given, called in /var/www/html/extensions/Wikibase/repo/includes/ChangeOp/ChangeOpsMerge.php on line 315",
    "errorclass": "TypeError",
    "*": "TypeError at /var/www/html/extensions/Wikibase/repo/includes/Merge/Validator/NoCrossReferencingStatements.php(25)\n#0 /var/www/html/extensions/Wikibase/repo/includes/ChangeOp/ChangeOpsMerge.php(315): Wikibase\\Repo\\Merge\\Validator\\NoCrossReferencingStatements->validate(Wikibase\\DataModel\\Entity\\Item, Wikibase\\DataModel\\Entity\\Item)\n#1 /var/www/html/extensions/Wikibase/repo/includes/ChangeOp/ChangeOpsMerge.php(151): Wikibase\\Repo\\ChangeOp\\ChangeOpsMerge->checkStatementLinks()\n#2 /var/www/html/extensions/Wikibase/repo/includes/Interactors/ItemMergeInteractor.php(160): Wikibase\\Repo\\ChangeOp\\ChangeOpsMerge->apply()\n#3 /var/www/html/extensions/Wikibase/repo/includes/Api/MergeItems.php(136): Wikibase\\Repo\\Interactors\\ItemMergeInteractor->mergeItems(Wikibase\\DataModel\\Entity\\ItemId, Wikibase\\DataModel\\Entity\\ItemId, array, NULL, boolean)\n#4 /var/www/html/extensions/Wikibase/repo/includes/Api/MergeItems.php(115): Wikibase\\Repo\\Api\\MergeItems->mergeItems(Wikibase\\DataModel\\Entity\\ItemId, Wikibase\\DataModel\\Entity\\ItemId, array, NULL, boolean)\n#5 /var/www/html/includes/api/ApiMain.php(1593): Wikibase\\Repo\\Api\\MergeItems->execute()\n#6 /var/www/html/includes/api/ApiMain.php(531): ApiMain->executeAction()\n#7 /var/www/html/includes/api/ApiMain.php(502): ApiMain->executeActionWithErrorHandling()\n#8 /var/www/html/api.php(87): ApiMain->execute()\n#9 {main}"
}