Hello. I can create custom record in UI, but when I try to create it using SuiteScript it shows me this error. "Items you have requested in the record have been deleted since you retrieved the form" I have commented all code snippet to set only the record name but still it shows that error message. Any help would be appreciated.

Likely some other user event or workflow on this record type is triggering that error

But in UI it did work?

Your script is likely failing to do something that is done by the UI and is expected by the other script/workflow