Hi @Iniobong Nkanga ,
Sorry for that. Until now, this is the only option to achieve this(To grant user1 access to Folder A1.1, 1. Add user1 as a reader to Folder A. 2. Manually remove user1 from all subfolders under Folder A except for Folder A1.1.).
I do understand it will cost you much time to complete all the process and it will affect your daily work. Apologize for the inconvenience caused on your side.
I could understand your concern and also quite agree it would be much more convenient if SharePoint can do what you describe. So I sincerely recommend sharing your valuable feedback in feedback portal. That is the specific platform where the developers can know which features are important to users. This is the best way to let developers know your requirements and comments, improve the product and make it better for you and others.
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