My washing maching,hotpoint aquarius 7 kg wmf740 door wont auto lock so cant work and flashing door on the display,can you advise what the possible problem is?

Hi from retired Englishman in SW France,

There is likely to be a problem with either the door solenoid/lock or the 'door closed' sensor. Either require a service engineer's attention I suggest ;-0(

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Thanks and good luck!
John C