RingOut problem - why did the "to" phone become the first leg and "from" phone the second leg?

We developed all features with RingOut API in sandbox for our web application. Yesterday it worked perfectly.Today strange things happened. When made call, somehow the "to" phone became first leg and "from" phone the second leg. The response after RingOut request was as something like

{
    "id": "Y3MxNjk2MTIzOTgyNDMyMTUyMDlAMTAuMjguMjAuMTEw",
    "uri": "https://platform.devtest.ringcentral.com/restapi/v1.0/account/~/extension/~/ringout/Y3MxNjk2MTIzOTgyNDMyMTUyMDlAMTAuMjguMjAuMTEw",
    "status": {
        "callStatus": "Invalid",
        "callerStatus": "Invalid",
        "calleeStatus": "Invalid"
    }
}Can someone let me know what went wrong?