disenchanted

US /ˌdɪs.ɪnˈtʃæn.t̬ɪd/
UK /ˌdɪs.ɪnˈtʃæn.t̬ɪd/
1.

no longer believing in the value of something, especially having learned of the problems with it:

:
•
Many voters have become disenchanted with the president.