fatal error when activating plugin

Hi,
this is the error message when I activate this plugin. It tells me before activation that it is compatible.

Fatal error: Uncaught SoapFault exception: [WSDL] SOAP-ERROR: Parsing WSDL: Couldn’t load from ‘https://prodws.deutschepost.de:8443/ProdWSProvider_1_1/prodws?wsdl’ : failed to load external entity “https://prodws.deutschepost.de:8443/ProdWSProvider_1_1/prodws?wsdl” in /home/fellnas6/staging/3/wp-content/plugins/woo-dp-internetmarke/includes/connectors/soap/ProdWS.php:72 Stack trace: #0 /home/fellnas6/staging/3/wp-content/plugins/woo-dp-internetmarke/includes/connectors/soap/ProdWS.php(72): SoapClient->SoapClient(‘https://prodws….’, Array) #1 /home/fellnas6/staging/3/wp-content/plugins/woo-dp-internetmarke/includes/Internetmarke.php(150): WCDPI\Connectors\SOAP\ProdWS->__construct(Object(WCDPI\Repositories\PartnerWpdb), Object(WCDPI\Repositories\ProductWpdb)) #2 /home/fellnas6/staging/3/wp-content/plugins/woo-dp-internetmarke/includes/Internetmarke.php(253): WCDPI\Internetmarke->initClasses() #3 /home/fellnas6/staging/3/wp-includes/class-wp-hook.php(286): WCDPI\Internetmarke->init(”) #4 /home/fellnas6/staging/3/wp-inclu in /home/fellnas6/staging/3/wp-content/plugins/woo-dp-internetmarke/includes/connectors/soap/ProdWS.php on line 72

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Please help!
Thank you!

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