Bosch washing machine (with issues) (Cambridge CB1 (coleridge))

Bosch washing machine Logixx 9. Washes up to 9kg, super fast spin cycle at 1600 RPM. Has been descaled regularly. The catch: Does its job perfectly well most of the time, but every couple of washes the detergent pump gets stuck and needs manual draining, takes about 10min. Anyone who is good with repairs is probably able to get it going again, but I can't.

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