That time between the data send of the two values is very likely to be too fast for the App to process - certainly too fast for the human eye to see. You should only need to receive a button press as a toggle.
Also, you are receiving a 0x01 ('1') and/or 0x00 ('0') - they are not signed bytes, they are unsigned bytes. Also, your call is in the Bytes Received Block (!), should be in a Clock Block, or you can use a Register For Bytes Block. Once the Bytes are received, the Bytes Received Block can update the Text Box.
It looks like you are also trying to set the Nordic status from the App?
You do not need to ask for Connect and Scan permissions because your App also has a BT Bluetooth Client and that component will add the permissions to the App's Manifest.
You do need to switch Fine Location on. You can do this manually or get the App to ask permission. If the App permission fails, add a location sensor component to your Project - that should force the permission to succeed.
Ensure that your UUIDs are identical in your Script/Sketch - they are case sensitive.