Hello,
Thanks for your message. We kindly ask you to contact our technical support team through our website, because the issue you’re having is related to an add-on of VikBooking (VikStripe), and not to the main plugin. Also, this is available only to the Pro/commercial version of VikBooking, and so in order to not go off-topic on this forum, we would appreciate if you could get in touch with our team through our website.
What we can tell you is that our VikStripe plugin was recently updated to the version 2.0.2. If you are using an older version, then you should consider updating the plugin to make sure session errors will not occur during the initialization of new transactions.
Our team can help you make sure the Stripe plugin is up to date, so feel free to get in touch through our website. Thank you!
The VikWP Team