How Salesforce expect to call the Rest API in Data Integration Specialist Superbadge

I'm doing the Superbadge - Data Integration Specialist and i'm stucked in the Challenge 6.

I've tried in two ways:

• Receiving the parameters in the URI (Query) appeding all the parameters

/services/apexrest/project?ProjectRef=Xpto_0002&ProjectName=ProjectTest&OpportunityId=0067Q0000069PNGQA2&StartDate=28022022&EndDate=31032022&Amount=5000&Status=Running

• Getting the parameter from Body Request

{
  "ProjectRef": "Xpto_0001",
  "ProjectName": "Project Test 001",
  "OpportunityId": "0067Q0000069PNGQA2",
  "StartDate": "28/02/2022",
  "EndDate": "31/03/2022",
  "Amount": 5000,
  "Status": "Running"
}

Both ways it's worked when calling the Rest Service from Workbench, but when i try to validate its fail.

Challenge Not yet complete... here's what's wrong:
The 'ProjectRESTService' Apex REST service does not appear to be working properly.
Calling the service either didn't update the opportunity correctly, return the string 'OK', create an associated project correctly or function correctly in general.

Does anyone knows how Salesforce expect the Rest Service should be build ? Or have a valid Payload format ? Because i have no idea what to do without these information ^^