Auto populate severity to high when Critical field is turned on

Summary:

We want Severity field to auto update to high when Critical flag is turned on.

I tried the below server script( Application Composer —> HR Helpdesk —>Server Script —> Trigger —> BeforeInsert), this is not working.

if (CriticalFlag == 'Y')
{
setAttribute('SeverityCd','ORA_SVC_HRHD_SEV1');
}

Can someone please guide or suggest the changes to achieve this?

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