@ContrarianValue44 I am sorry but I mixed it up. I actually meant Türk Telekom, which entered the German market via a joint venture with O2 (Telefonica Germany) several years ago but wasn't a success at all. Apparently, Türkcell is still operating in Germany after rebranding itself. https://www.telekom.com/de/konzern/details/aus-turkcell-europe-wird-lifecell-511830
But I would still assume their revenues in the German market are negligible as the big three MNOs Deutsche Telekom, O2 and Vodafone share the market among themselves.