Are you talking about the neighbouhood tasks - gives SP/XP
or
Weekly tasks? - Finish all within the week and get a key
Neighbourhood task
make sure you sim has reached the phone at you neighbours town before going back to your town
maybe the phon is inaccessable and you start the task and leave before the blue footprints appear
if that is the case try to find another phone
Weekly task
make sure the Sim you are using does NOT live in the house with the phone
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