Hello @strigga,
My name is Henry Eduardo and I am happy to assist with your inquiry, and appreciate you contacting LastPass Support!
I am sorry about the issues you are having with your account. Can you please follow the steps to do the export using the browser extension instead. You can find them on this article.
Please let me know if this worked or if further assistance is required.
Thank you,
Henry Eduardo | Customer Care
Thank you, that worked.