Search for “Resdential Tenancies Act 2010” on the NSW Legislation web site.
Division 4. Sections 55 to 61 are relevant to your question.
Section 55 Paragraph 2 says that the landlord can enter the premises to do maintenance if they give the tenant at least two days’ advance notice.
I suggest you read through this yourself and see if there is a way you can remedy the situation. Perhaps a polite request to the landlord supported by a letter from your GP or specialist doctor would be enough.