Not a valid VCALENDER errror during calendar creation

Hi all

I try to added a new remote calender. When I klick on "Load iCal from URL" button I get messages
file_get_contents() failed, try fsockope
Not a valid VCALENDAR data file: Not a valid VCALENDAR data file: httpshttp://www.swiss-badminton.ch ....

When I insert the URL into an existing calendar all went well.

PHP Version : 7.1.20

MySQL Version : 5.5.5-10.1.34-MariaDB

Server Information : Linux saphir.metanet.ch 3.10.0-862.9.1.el7.x86_64 #1 SMP Mon Jul 16 16:29:36 UTC 2018 x86_64

Fix jQuery? : Yes

Load JEvents Bootstrap CSS? : Yes

Club code set? : No  

User Agent : Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:61.0) Gecko/20100101 Firefox/61.0  

Joomla : 3.8.11

component_com_jevents : 3.4.47

component_com_jce : 2.6.8

module_mod_jevents_cal : 3.4.47

module_mod_jevents_custom : 3.4.47

module_mod_jevents_filter : 3.4.47

module_mod_jevents_latest : 3.4.47

module_mod_jevents_legend : 3.4.47

module_mod_jevents_switchview : 3.4.47

plugin_content_jevents : 3.4.47

plugin_finder_jevents : 3.4.47 (not enabled)

plugin_installer_jeventsinstaller : 3.4.47 (not enabled)

plugin_search_eventsearch : 3.4.47

plugin_system_gwejson : 3.4.44

I searched forum for a solution, but no success.

Thanks for your support
dancat