Fatal error with session name when activating plugin

I haven’t been able to activate the plug-in because I am getting this error:

Warning: session_name(): Cannot change session name when session is active in /home/xhjjheqr/public_html/wp-content/plugins/booking-system/framework/includes/class-session.php on line 129

Warning: ini_set(): A session is active. You cannot change the session module’s ini settings at this time in /home/xhjjheqr/public_html/wp-content/plugins/booking-system/framework/includes/class-session.php on line 134

Any ideas how to solve this issue?

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