I tried again, I downloaded the file that works in my Phyphox app installed on my phone using the three dots option, I uploaded it again using the Editor and again it didn't work.
I did it again but checked the parameters of the Bluetooth module, without changing anything and re-uploaded it to the app and this time it
worked.
For each test, I reset the Editor screen, I also downloaded the .phyphox file and reviewed them, I found that they were not the same regarding the Bluetooth module, these were the differences:
Solo_FotoCeldaTest.phyphox (don'work):
<input>
<bluetooth name="Arduino MKR 1010" uuid="19b10000-e8f2-537e-4f6c-d104768a1214" rate="0">
<output char="19b10001-e8f2-537e-4f6c-d104768a1214" conversion="singleByte">Time</output>
<output char="19b10001-e8f2-537e-4f6c-d104768a1214" conversion="formattedString" separator="/" index="0">Fotocelda</output>
</bluetooth>
</input>
Solo_FotoCeldaTest (1).phyphox (WORK):
<bluetooth name="Arduino MKR 1010" uuid="19b10000-e8f2-537e-4f6c-d104768a1214" mode="notification" rate="0">
<output char="19b10001-e8f2-537e-4f6c-d104768a1214" conversion="singleByte" extra="time">Time</output>
<output char="19b10001-e8f2-537e-4f6c-d104768a1214" conversion="formattedString" separator="/" index="0">Fotocelda</output>
</bluetooth>
I am attaching both files: the one that didn't work (Solo_FotoCeldaTest.phyphox) and the one that did (Solo_FotoCeldaTest (1).phyphox).
It seems that the Bluetooth module is still unstable

.
I attach data captured with each of the versions of the .phyphox files (incorrect and correct).