The separate user entries probably occurred when the CPIDs split after the projects were marked as retired; you can check the "BOINCstats > Sync retired projects" function to see if you can pull some of those orphaned IDs back into your main account. Unfortunately, this only works if you had the project attached to BAM (just on the account page, you don't actually need to use the account manager on your hosts) when the project(s) were marked as retired. That was a requirement added to confirm your identity, so that someone couldn't make an account with your name and steal your credit.
Thanks Noderaser. Unfortunately, there is nothing I can do to change this at my end since those projects with different CPID are not listed in Sync retired projects. The security feature works too well. It seems that Cruncher Pete (The only one) has stolen Cruncher Pete's account and in one account he even exists twice in the same team. I always used BAM since the beginning and I had to change my email address once because I changed my ISP and I had to change my password another time because my account was compromised and somebody deleted a project of mine. These are all necessary changes but it seems that if you do it you will loose some of your hard erned credits. I feel like somebody stole my credits. Cruncher Pete is the culprit, please give back the credit you stole to Cruncher Pete...