I have found many people had low salinity recently due to mis calibrated refractometers. The problem all came from these meters’ user manuals called for calibration using RODI or distilled water. When these meters were calibrated with distilled water, they read high when using 35ppt calibration standards.
I am using a Refractometer calibrated with 35ppt standard and cross reference to a calibrated Hanna salinity checker.
Also, it can be a good idea to calibrate your salinity probe frequently if you are using one.