I honestly need to change banks

Can someone explain to me how is it that money that an amount that was paid into my account does not reflect on my account then I'm being told I received it when I hadn't received it.. I honestly need to change banks cause money just disappears then nothing is don't about it.. I also had an incidents months back where unknown ransactions that where made from my account I never received any assistance all I was told was that they can't do anything as those transactions were made from my account