Steps to reproduce:

1. https://www.zabbix.com/documentation/current/en/manual/api/reference/event/get#retrieving-events-by-time-period
2. This example uses "desc" for sorting order
3. Response shows items in ascending order

Result:

Expected:
Request in example should use all-caps "DESC".

Response contains events in descending order, same as the description above the example.