Reshape data from wide to long (Creating Panel Data)

I downloaded data from data stream Refinitiv. The data is in wide format which resulted in too many variables (761). I only want to form 8 variables.


How can I do that in Stata?


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I wrote this syntax
reshape long Date variable, i(date) j(UVBKP, PCHUVBKP1D, UVBKPA, UVBKPB, UVBKTNA, UVBKNAV, UVBKPH, UVBKPL)



but I don't know why it says
variable date not found
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