DIPLOMAT DISHWASHER BUZZER CONSTANT?

THANK YO FOR ALL YOUR ADVICE, BUT WE HAVE HAD THE COVER OFF AND NO WATER IN TRAY, TRIED THE RESET , SWITCHING IT OFF AND ON, TRIED THE PRESS 4 TIMES, CHECKED PIPEWORK NO KINKS IN PIPEWORK, NO MATTER WHAT PROGRAMME I PUT IT ON , IT STARTS FOR A FEW MINS, THE IT STARTS BEEPING CONSTANTLY, AND WHEN YOU OPEN THE DOOR THE RINSE LIGHT IS ON, PLEASE HELP, I KNOW LAST TIME IT DID THIS IT COST ME A £50 CALL OUT CHARGE , AND ALL HE DID IS WHAT YOU GUYS HAVE SAID, BUT ALSO TOLD ME I NEEDED A NEW PUMP, OVER £100 IN THE END, HAD THIS A LONG TIME, AND HAVE HAD PROBLEMS IN THE PAST , BUT HAVE ALWAYS BEEN ABLE TO SOLVE IT,