Non EEA PR refused, appeal or reapply? Pls help

I am new to this forum. I will be grateful if I could have some advice from the members.

My parents EEA PR application was refused as we don’t live in the same address. They are 100% financially dependent on me and they are currently living 10 walking distance from us. Their flat is owned by me and I am paying the mortgage. My London flat is not big enough to accomdate them. We have a joint account which proves the financial dependency.

I found the reason HO refused the application is unacceptable. I would like to know what is the best option for me, to appeal or reapply? If I have decided to reapply, is there a timeline to be respected? For appeal I have to do within 14 days from the dated letter. Any help will be greatly appreciated!