Translation:She also informed her bank.
Why is it "a su banco"? Is this the personal "a"? If so, does an entity like a bank qualify in using that grammar construct?
You use the personal "a" because she´s informing the people working at the bank. If there was no "a" then it would be implied that she is informing the actual building.
Why isn't "She also informed your bank" also correct?
i believe that is correct also