It's a common problem in these days i think you need to tell about problem a good technician who can solve it and able to provide good solution of it. Results fluctuating while measurement it's not a good sign and cause of many other problems.
Great technique works behind the working of load cells .This page really helpful for those who want to had some information about load cells how it works.IF i am not wrong it's about double ended load cell which are commonly used in these days .