Yes it should work with the same password and if yours isn't, something's gone amiss. I wonder if you can be signed into the site both through the app and safari at the one time, just a thought in case you are. Well to start I would close the app completely and relaunch it. From the home screen do the four finger swipe up or double press the home button to reveal your multi task bar. These are all the apps that you have opened at one time. Long press the app until it jiggles and a red minus sign will appear above it. Press the minus sign, this will close the app, not delete it. If that doesn't work a Restart and or Reset are the next steps. Let us know how you go.
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