Unable to Mask data after applying mask function in Azure Synapse table

I have created table prd.CustomerDimension CREATE TABLE [prd].[CustomerDimensions] ( [WWI Customer ID] [int] NOT NULL, [Customer] [nvarchar](100) NOT NULL, [Bill To Customer] [nvarchar](100) NOT NULL, [Category] [nvarchar](50) NOT NULL, [Buying Group] [nvarchar](50) NOT NULL, [Primary Contact] [nvarchar](50) NOT NULL, [Postal Code] [nvarchar](10) NOT NULL, [Valid From] [datetime2](7) NOT NULL, [Valid To] [datetime2](7) NOT NULL, [CreditLimit] [decimal](18, 2) NULL, [PhoneNumber] [nvarchar](20) NULL, [FaxNumber] [nvarchar](20) NULL ) WITH ( DISTRIBUTION = REPLICATE, CLUSTERED COLUMNSTORE INDEX ) GO Trying to apply Mask on column PhoneNumber using below query: ALTER TABLE [prd].[CustomerDimensions] ALTER COLUMN [PhoneNumber] ADD MASKED WITH (FUNCTION = 'default()'); The query gets executed successfully but when i fetch data from the table it shows original data only no masking is applied. Even applied mask function while creating table but still not able to mask column. Please help me to figure this out.