The validation error CMN.ATO.SMSFAR.436654 you are receiving is in regards to the supervisory levy amount. If a fund was wound up during reporting year, Supervisory levy adjustment must be $259. Labels L, M and N are used to calculate the amount of SMSF supervisory levy that the SMSF must pay with the 2020 SMSF annual return. The amount that you must write at each of these questions depends on the status of the SMSF. Please refer to the below ATO link:
https://www.ato.gov.au/Forms/Self-managed-superannuation-fund-annual-return-instructions-2020/?page=51
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