Calendar Base Error

Message: Missing or wrong parameter. The event you are looking for could not be found.

Note: Please verify your URL parameter: tx_cal_controller[uid]

URL:http://www.gruene-osterholz.de/ortsverbaende/ortsverband-schwanewede/home/termine-ov-schwanewede/cal/event//tx_cal_phpicalendar/2019/02/27/jahreshauptversammlung-e7c0932447/