makeImageRequest doesn't work in FR965

Hi, there are a least 4 FR965 users reported to me that the Avak watch face didn't download the custom background image. I use the API makeImageRequest. Sometimes the API returns -104 (BLE_CONNECTION_UNAVAILABLE), some other times -1 (BLE_ERROR), but most of the time it's 0 (UNKNOWN_ERROR). I didn't hear a successful download from any of my FR965 users. Would you please check if the API works properly on FR965? 

Thank you for your help.