I didn't get Brint/Brienne's Ring after marriage

[Off The Record]

I married Brienne, Rina, and Cassia. Did I need to marry her alone for the ring?

 

[IraMorti]

You have to go back to Brienne at their home and talk to her, she'll eventually give you the ring.

 

[ballin]

You have to go back to Brienne at their home and talk to her, she'll eventually give you the ring.

i've gotten the ring at the frosthound so i'm pretty sure you just need to talk to them after the wedding