Hi Mike, my name is ***** ***** I will assist with your query today.
The aqua stop should show up as a separate error code as its a flood detector.
In the majority of cases where the fault is not a kinked inlet pipe and the water supply is working, its the valve\actuator which has failed.
A new actuator can be sourced from espares.com in the most part, they are rather straight forward to replace and easy to check, as you just check when you turn the washer on, that your getting a voltage to the two terminals.
A generic video can be found here which shows you what is required to replace the valve, as you will see its not a big job, so not really needing an engineer if your competent with a screw driver. The video here, though aimed at dishwashers shows the general steps to take to test the valve itself, so you can be sure the part is faulty before ordering a replacement.
Should you wish me to recommend an engineer please provide your postcode, if you cna also supply the ENR I will try and track down the exact part you need to.
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