Issue with a blueprint transition using API request

Hello

I have created a function in the Zoho Flow app, which should perform a blueprint transition.

par = Map();
par.put("toNotifyContactForResolution",false);
par.put("content","Solved");
param = Map();
param.put("RESOLUTION",par.toString());
result = invokeurl
[
url :"https://desk.zoho.com/api/v1/tickets/xxxxxxxxxxxxxxxxxxxxxxxxx/transitions/yyyyyyyyyyyyyyyyyyyyyyy/perform"
type :POST
parameters:param.toString()
connection:"zoho_desk"
];

This code is pretty simple. It works well if a ticket assigned to the Primary user. If I assign the ticket to another user, the request fails.

{
	"errorCode": "INTERNAL_SERVER_ERROR",
	"message": "An internal server error occurred while performing this operation."
}

At the same time both of the users can perform the transition manually using the buttons in the application. The error appears only during the API request.