Magnet Tool + GPS/GNSS Post Processing

I am processing multiple GPS/GNSS using two base station and a IGS station. Some of the direction are reverse from rover to base and cause big magnitude of errors. Its quite confusing. while checking the GPS Obs properties, i identified that some of them were rejected by heights, some by Horz and some are failed to match the desired precision. Please help me to sort it out. This is my masters project?ÿ and am very happy to be part of the team to seek assistance.