I'm Unable to get Centimeter level accuracy from ZED F9P although using all the configurations mention in the integration manual

[piyush-agarwal-85]

I am using 2 ZEDF9P for getting centimeter level accuracy. The base is directly connected to the rover via UART2, as suggested in the integration manual of ublox. I have all the necessary messages enabled on the base and rover, also given in ublox datasheet. Ucenter is even showing Fixed solution, but still after mapping those coordinates, the readings are inconsistent. Both rover and base were kept 3-4m apart in static position and the base is configured in SurveyIn mode.
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