Some apps not updating, Asks for ID password and says its incorrect or just does nothing. I have never changed my apple ID.

Hello, this is a problem that is annoying me and can't find a solution. I have an Iphone 4S

Ever since my first apple device, I registered with my ID, Which I have NEVER changed. I cannot pinpoint the exact time in which the app store updates started giving trouble. It started asking for my ID password, but showing me an incorrect ID, just ONE letter was wrong. Seemed weird because i did not have problems with my mails and purchases. Then, it was correct, but the apps that were purchased before would not update or download, because of the incorrect ID. I left it alone because in the mac store or anywhere else no one could help me. I had to re-purchase some apps. Now a similar problem is happening. When I try to update my apps, for some apps it prompts a message asking for my password, showing the CORRECT ID. and when I input an old passw, or an incorrect it says it is incorrect. BUT when I input the CORRECT passw, it does nothing, no prompts, no updating no waiting. The circle thing that appearsin the app store when waiting to update just reverts to the update button. Please help me. thanks.