You are trying to subscribe to a Bookeo paid plan and get the error message the payment could not be processed. Reason: 05 Do Not Honour - this error message is issued by your card issuer and means the merchant (us) should not allow the purchase.
There is a problem with your account. You can call your bank. Ask them to explain why they refuse to authorize the purchase. If there is a restriction on shopping outside your country tell them to remove this and immediately. Often we see the same account number worked for a previous purchase and a renewed card does not. This is a matter for the bank to fix.