According to the company, you can cancel your subscription to COSMOTE TV or MAGENTA TV by calling customer service at 13888, visiting a physical COSMOTE/Germanos store, or electronically through the official COSMOTE website.
telephone: Call 13888 (toll-free from COSMOTE network).
In Store: Visit any store in the COSMOTE or GERMANOS.Online network /
Electronics: Submit a termination request through My COSMOTE






My experience is exactly the same.