It’s not quite clear, but their ToS (http://www.mobpartner.com/en/publisher/terms-of-service) state that your account will be deactivated or deleted (?) after not logging in for 30 days.
If you’re not certain after having tried this, or anyway, contact them immediately with your request: http://www.mobpartner.com/en/company/contact
URLS:
http://www.mobpartner.com/
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