My multibit wallet is bugged please see

[Kyraishi]

Hello
I have a multibit wallet.
And i have 0.03 btc one of the adress.
But it show more btc than i have (0.20)
But i can't use the 0.03 which is mine.
And oh i have a adress in my wallet which isn't mine, what's wrong ?

Everytime i try to send i get "script didn't match expected form"

Please help
Thanks

[Kyraishi]

Solved it by exporting private key but still i would like to ask if anyone know why do i have a adress in my wallet which isn't mine ?