PHP SDK for webflow cms API

link to SDK repository - GitHub - expertlead/webflow-php-sdk: PHP SDK for the Webflow CMS API
I’m having a problem when trying to update a CMS item using updateItem function,
I get no response and “HTTP ERROR 500” ,
I also tried to create an item (createItem function - to the same collection) with the same “fields array” that I used for updateItem and it worked.
What am i supposed to do in order to make updateItem function work?
it seems that the array i put in the updateItem function is wrong.
Any ideas ?
Thank you very much.

I suggest you open an issue with the github maintainer. This is custom code.