The road use authorization can be purchased during the NMPS outage as well at resellers (e.g. fuel stations) or at the website https://ematrica.nemzetiutdij.hu/, and parking can be paid at parking meters.
Please note that the maintenance or the outage of the mobile payment system does not qualify as a reason for not purchasing an e-vignette, a HU-GO route ticket or a parking ticket. Please do not forget to pre-purchase the road use authorization during this period, either! You must already have a valid authorization when entering a toll section.