When DAVdroid queries the server for events since Sun Jul 15 12:06:04 GMT+02:00 2018:
2018-10-13 12:06:04 381 [syncadapter.CalendarSyncManager] Querying events since Sun Jul 15 12:06:04 GMT+02:00 2018
2018-10-13 12:06:04 381 [HttpClient] --> REPORT https://mailfoo.example.com/cal/username%40example.com/main/
2018-10-13 12:06:04 381 [HttpClient] Content-Type: application/xml; charset=utf-8
2018-10-13 12:06:04 381 [HttpClient] Content-Length: 328
2018-10-13 12:06:04 381 [HttpClient] Depth: 1
2018-10-13 12:06:04 384 [syncadapter.SyncManager] Sent 0 record(s) to server
2018-10-13 12:06:04 381 [HttpClient]
2018-10-13 12:06:04 381 [HttpClient] <?xml version='1.0' encoding='UTF-8' ?><CAL:calendar-query xmlns="DAV:" xmlns:CAL="urn:ietf:params:xml:ns:caldav"><prop><getetag /></prop><CAL:filter><CAL:comp-filter name="VCALENDAR"><CAL:comp-filter name="VEVENT"><CAL:time-range start="20180715T100604Z" /></CAL:comp-filter></CAL:comp-filter></CAL:filter></CAL:calendar-query>
The server responds with an empty multistatus
XML, i.e. not a single event:
2018-10-13 12:06:04 381 [HttpClient] <-- 207 https://mailfoo.example.com/cal/username%40example.com/main/ (60ms)
2018-10-13 12:06:04 381 [HttpClient] server: nginx/1.14.0
2018-10-13 12:06:04 381 [HttpClient] date: Sat, 13 Oct 2018 10:06:05 GMT
2018-10-13 12:06:04 381 [HttpClient] content-type: text/xml; charset=utf-8
2018-10-13 12:06:04 382 [syncadapter.SyncManager] Removed 0 local resources which are not present on the server anymore
2018-10-13 12:06:04 382 [syncadapter.SyncManager] Post-processing
2018-10-13 12:06:04 382 [syncadapter.SyncManager] Saving sync state
PARAMETER #0 = {"type":"SYNC_TOKEN","value":"http:\/\/radicale.org\/ns\/sync\/cc5b729aee83bc1153fac132a40e63f3"}
2018-10-13 12:06:04 381 [HttpClient]
2018-10-13 12:06:04 381 [HttpClient] <?xml version='1.0' encoding='utf-8'?>
<multistatus xmlns="DAV:" />
2018-10-13 12:06:04 381 [HttpClient] <-- END HTTP (67-byte body)
So, the server tells DAVdroid there are no events. This is probably a server problem.