PHP Fatal error: Uncaught Error: Class ‘Rsc_Http_Request’ not found

Hi,
strato log file shows me the following error messages:

PHP Fatal error: Uncaught Error: Class ‘Rsc_Http_Request’ not found in /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-content/plugins/data-tables-generator-by-supsystic/vendor/Rsc/Resolver.php:40

Stack trace:
#0 /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-content/plugins/data-tables-generator-by-supsystic/vendor/Rsc/Environment.php(98): Rsc_Resolver->__construct(Object(Rsc_Environment))

#1 /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-content/plugins/data-tables-generator-by-supsystic/app/SupsysticTables.php(21): Rsc_Environment->__construct(‘st’, ‘1.9.76’, ‘/mnt/web423/b0/…’)

#2 /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-content/plugins/data-tables-generator-by-supsystic/index.php(29): SupsysticTables->__construct()

#3 /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-settings.php(342): include_once(‘/mnt/web423/b0/…’)

#4 /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-config.php(124): require in /mnt/web423/b0/15/59914215/htdocs/2019-05-08_08-15-45_6Z5YRN4K04/wp-content/plugins/data-tables-generator-by-supsystic/vendor/Rsc/Resolver.php on line 40

What exactly is the problem and how can I solve it?
Thanks for your help!