T5013, how to find fiscal year start date. Tried 1/01/ 2021 and other within 12 months and none is accepted?

Show me if end fiscal period end is 31/12/2022, what will system accept as Fiscal period from?

Self-employed

If your fiscal year end is 31/12/2022, then the start would be 01/01/2022, not 01/01/2021. Enter the dates with numbers only, no slashes.