NCA slapped the ban on Expresso after it failed the quality of service tests in the Volta, Eastern and three Northern regions.
Expresso has till the end of this month to fix the challenges.
Concerns have been raised as to why the ban was not restricted to the areas where they failed the test.
Director of Consumer and Corporate affairs at the NCA, Nana Defia Badu explaining the reason for the nationwide ban to Citi Business News said ‘if a network is down in an area, it doesn’t mean that only the consumers in that area are affected. It is also possible that other consumers from other parts of the country may be trying to reach those within that area that have been affected and they will not be able reach them”.
Expresso has the least market share of about 154,000 subscribers measuring about 0.54 percent of Voice mobile subscribers in Ghana.