If stored procedure is working fine in SQL Server but taking long time in SSRS, use the command "With recompile" in stored procedure like:
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Create PROCEDURE [dbo].[spGBRGetAllCallRecords]
@pMSISDN varchar(50),
@pStartDate datetime,
@pEndDate datetime
with recompile
AS
SET FMTONLY OFF
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Create PROCEDURE [dbo].[spGBRGetAllCallRecords]
@pMSISDN varchar(50),
@pStartDate datetime,
@pEndDate datetime
with recompile
AS
SET FMTONLY OFF
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