According to what I gathered, Kunle Afolayan was booted out when Globacom found out that one of the main characters in his Phone Swap movie (which was sponsored by Globacom) was Saka, an Etisalat face for many of their brands, at the time. (Before he ported to MTN )
Prior to him being dropped as an ambassador, Kunle had a smooth relationship with the company and did not go against any terms in his contract and was really shocked at his termination. Thing is, Kunle had been working on his movie long before he was approached to be a Glo ambassador.
Globacom sponsored the movie and when it eventually came out and they saw Saka in it, that was it!