it certainly does not seem to me that this what you describe is the correct behavior. the most obvious thing, and i am sure you don't want to hear it, is that you are not entering it correctly. it happens. but if that is all i was going to say i wouldn't bother. here is what i think you should do. someone more knowledgeable might pop up, but i see it has already been here for 7+ hours without a response.
take a cautionary step and launch safari and look at preferences security under the safari menu item, not under the apple. browse thru all the id's and use your machine pw to inspect every item that is related to an applied or iba or iTunes connect to see if there is some discrepancy. it will also allow you to verify your pw.
step1: try again via iba with your apple id and pw, both with iTunes connect/safari and iTunes connect/iba.
step 2. if it still does not work, go to iTunes connect/iba and recover your password i.e.. change it. it will be a bit of a pain, because i think you will be prompted on all your devices eventually to reenter your applied/pw.
step 3. this should get you in. if it does, go to step 4. if it does not, call apple iba support.
step 4: at some point, use this apple id and new pw to get into iTunes connect/safari. if ok, go to celebrate. if not ok, call apple iba support.
hmm ... what version of iba are you using? you can also send your book to the store by using iTunes producer i think. i haven't done so myself, but am close to having to do so with my second ebook and will investigate this more, as it wasn't available i think when i submitted my first book many moons ago.