Question moved from MISC.
I live in Toronto!
Try removing the key and reinsert it.
The KETTLER treadmill has an emergency stop mechanism for
your safety. Before starting your workout, fasten the cord of the
safety key to your clothing. If the treadmill has been shut down
by removing the safety key, restart it by reinserting the key. An
automatic restart of the treadmill belt does not occur. Further
instructions concerning the handling of the safety cut-out can be
found in the operating instructions for the training computer.
https://manuall.co.uk/kettler-toronto-treadmill/
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