Help with doubt about Rakuten Tickets

I’ve bought tickets for a piano recital in Tokyo through Rakuten, but have a terrible doubt: When I bought them, the option to reserve seats was greyed out and the kanji said that the all seats were reserved (全席指定).

I took it to mean that there were no reserved seats (first come first serve) but now that the date is approaching I’m getting worried about it (maybe it was a case of overbooking or maybe I bought it wrong).

Can anyone with experience with these matters confirm if I was right about the seats not being reserved?

Thanks!