Hello again.
As per your past topic, Bluetooth and BLE are reported as in BETA… useable but with little glitches that could be as much due to the BT/BLE hardware & phones (I use multiple Androids) as the software.
In my testing with an Arduino UNO & JY-MCU (linvor) Bluetooth Module as well as Light Blue Bean BLE setup, I have noticed that I often must stop and restart the project to reconnect (even if it says connected) after either time has passed, or if exiting the app (via the home button or something - not logging out or stopping project) and even if something times out due to data flooding… but without the same error tracking as would probably be noticed with a traditional App <–> Server <–> Device setup.
I have also noticed times where I have has to “stop” the project twice before it actually showed as stopped with the App icon.
I find it best to keep an Up-Time display running to keep me notified if the connections is active or not, instead of assuming based on the normal indicators.
There are even times when the up-timer stops, but if i press a button or move a slider, etc, then after a few seconds everything continues on and looks active again.
As I said… little glitches here and there… BETA 
I am sure the developers are working on this, but as BT/BLE is not really an ideal “Control your IoT stuff while roaming around the countryside” solution, as is WiFi and GSM, they may? have it on a lower priority list.
Meanwhile continued and detailed info on what happened and how you recovered would probably be helpful.
Also, where possible, please post any images directly to the post instead of 3rd party cloud sites. Just easier for anyone glancing through posts to see. Thanks.
PS - I copy/pasted your screenshot into your post, in case you were unsure of how to upload images yet.