AutoRest.PowerShell code has the logic to keep GUID reused when building a module. The issue was caused by the psd1 indent. It searched GUID in the psd1 to see if a GUID existed. When a psd1 is updated by Update-ModuleManifest, the 2 spaces before the GUID will be removed. Thus it considered there was no GUID generated.
AutoRest.PowerShell code has the logic to keep GUID reused when building a module. The issue was caused by the psd1 indent. It searched
GUIDin the psd1 to see if a GUID existed. When a psd1 is updated byUpdate-ModuleManifest, the 2 spaces before theGUIDwill be removed. Thus it considered there was no GUID generated.