Definitely should cache the old balance though. Nunchuk takes some time to check new balances but my old ones don’t go away. With people so scared of using bitcoin, mitigating that sort of fear of “OMG MY WALLETS EMPTY” is probably a good idea.

Otherwise it makes sense it takes  while to find all the new transactions. 

 You can turn it off or adjust the settings of how far back you want it to search 
https://image.nostr.build/69ea51160fbfe600da9092f3b90681449fb38de852382096d6621b964186fa21.jpg