No. series is not working

Dear Experts,

In my dimension master there have a dimension the name is "RND". Against RND dimension I want to run the no. series to generate the dimensions value.

Code, I have added it but it is not working. no. series is not generating automatically. In my table 349 I have added the below code:

OnInsert()

//Generate No. series BEGIN
SalesSetup.GET;
NoSeriesCode := '';
IF Code = '' THEN BEGIN
NoSeriesMgt.InitSeries(SalesSetup."R&D Dimension No. Series",'',WORKDATE,Code,NoSeriesCode);
END;
//Generate No. series END

Here all variables are below:

Name                  DataType         Subtype Length
SalesSetup           Record            Sales & Receivables Setup
NoSeriesMgt       Codeunit         NoSeriesManagement
NoSeriesCode     Code              10