The reason you are getting this error is because you do not have a cryptocurrency wallet installed on your computer or mobile device. If you do not have a cryptocurrency wallet installed, your device/computer will not know how to handle the link behind the Pay In Wallet button.
To complete the payment, you can scan the QR code using a mobile wallet or use the copy button on the invoice and then paste the payment details into your wallet. View our support article on the ways to pay an invoice.
For assistance with choosing a wallet to install on your device, please view the following help article.