Fujitsu MESSHU RT500 Faq page 25

6.1.
If the phone hasn't turned on the Bluetooth, a
message will pop up asking if you want to turn it
on, select "Yes"
6.2.
If there is a router connection failure, it means
that the APP does not find any router that can
be paired. Please confirm whether the Router
LED is flashing blue or not. Or refer here
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