Thank you Robert, I forgot to tell that I created the model from zero. Using the same tools and parameters but I didn't import it directly from the one that I use in Arcmap. The release of ArcGIS Pro is 2.9.3 and of Arcmap is 10.6.0.8321
Anyway, I will run the Analyze Tools to check all the model and see if everything is ok.
Update: The result was:
Analyzing toolbox APC6034(C:\XXXXXXXXXXXX\.tbx) for use within ArcGISPro:
WARNING 001681: Found REMOVED Layer File C:\XXXXXXXXXXXX\Simbologia_Rutas.lyrx within model tool SimbologiaOrdenesRutas_APC6034
WARNING 001681: Found REMOVED Layer File C:\XXXXXXXXXXXX\Simbologia_Ordenes.lyrx within model tool SimbologiaOrdenesRutas_APC6034
That Toolbox contains 4 models where those layer files are used for the fourth one. The third is the one that updates the information in the geodatabase. According to those results, the models have no incompatibilities because, in fact, I also made the others completely new, from scratch. They were not imported.
So I still can't locate the error 😞