Deutsche Telekom’s unit in Poland was hit with a PLN25.6 million ($6.4 million) fine by the country’s competition authority for an allegedly misleading advertising campaign claiming to offer 1,200GB of free data for a year.

In a statement Poland’s Office of Competition and Consumer Protection branded T-Mobile’s advertisements of “1,200GB for free a year” misleading, concluding the suggestion was users would get the credit for free when in fact it required a top-up.

It explained customers had to credit prepaid accounts with PLN35 per month in order to receive 100GB of free data for the month. The authority added although this fact was published at the end of the adverts, the information was “printed in tiny font at the very bottom”.

The advertisement appeared on various billboards and public areas in both Polish and Ukrainian.

The regulator’s judgement is subject to appeal, with several local media outlets suggesting T-Mobile Poland intended to contest it.

Should the decision be upheld, the operator must publish the decision on its social media channels and on its website in both languages the adverts appeared in.