The most probable reason for it is the way you are signing the request itself. To find the examples of how it should be done please follow the link or this one.
In case it is not the case or you think that something else is wrong please contact us writing to support@currency.com and provide us with the example of the request showing the way you sign it and we will get back to you.
I received an error saying 'Invalid API-key, IP, or permissions for action'. What can be the reason for it?
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