@diana_diaz it could be that if the estimator trusted the gps position more, navigation failures like that would not happen. But it’s just a somewhat educated guess. I suppose it would not hurt, at least.
However my issue seems related to startup, and yours happening in-flight, so I think it has different rootcauses. We also experienced navigation loss in-flight (like this one), but rarely having an error in the range of kilometers. Could it be that your UAV thought it is “back at its base”? We have had that isue happening as well, but that included the GPS’s fix type to drop to 0, maybe that’s one thing to check (even though the gps coordinates seemed correct).