The telecom regulator, CNMC, has ordered Vodafone Spain to adjust its prepaid roaming plans to meet EU standards.Vodafone Spain had reduced the amount of free-roaming data available to prepaid customers traveling within the EU.CNMC's investigation found that Vodafone's data allowances for roaming were significantly below the legal threshold.Vodafone has been given 10 days to outline the adjustments it will make to comply with EU regulations.