As Stephen mentioned, it depends on the Field Status Group (FSG) assigned to the G/L account you are using.
To overcome this issue, I recorded a script using a specific G/L account where all fields were optional. In my case, the field status group of this G/L account was G999 and I think this is not standard SAP so might not be same in your organization. You can check all FSGs in SKB1 table and go from there.
@Winshuttle Support might have a better solution.
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Younus Ahmed | Data Quality Analyst
Smith & Nephew, Business Services
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