What steps do you take when your paycheck bounces? Continue to work?

Payroll said that I was not on file?! They said they would correct the problem and that I should try to re-deposit the check. I contacted the bank and they wanted me to try to redeposit the check as soon as I receive it. Note that this is all based on a verbal comment from payroll that the problem has been corrected and I should re-deposit the check. If they are somehow messing with me to have me work longer before I quit, what urances do I have that they will pay me for back wages or for any work that I am doing in the interim. Note that I had taken a business trip also and they have not re-imbursed me for that either even though the status of the business expense is showing as paid. In that case, payroll is sending me on a wild goose chase to Accounts Payable. However, from what I gathered from other coworkers, the reimbursement comes directly in the paycheck. I am thinking there is something strange happening and I should be extremely cautious. Any advice would be greatly appreciated.