I have the same type of problem and it maybe as in my case old age or ' automatic pilot syndrome', where the brain switches off when you are doing repetitive tasks eg how many times do you go into the kitchen to make brew and then when you get there you can't think why you went in there.
I have a further problem, its called Sue and no matter where I put something down its always in the wrong place and moved without telling me. Strangely it never applies to anything she puts down, even when we both know it's in the wrong place
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