How can I check the correct balance on my new wallet?
Isn't it suppose to show the total balance for the wallet on the bottom left corner?
Would it be possible to sign from the missing change addresses?
I never had this experience however from common sense it should work since the address is associated with the same wallet/seed. May be it does not show by default. If you know the address then why don't you try a test sign for the address?
Good luck.