I doubt the issue is with your choice of UUID's.
See some example code here
https://forum.arduino.cc/t/ble-code-to-take-string-input-from-another-bluetooth-enabled-deice/643877/2
I doubt the issue is with your choice of UUID's.
See some example code here
https://forum.arduino.cc/t/ble-code-to-take-string-input-from-another-bluetooth-enabled-deice/643877/2