Seeking expert advice on Rosemount 5400 series radar level gauges

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Currently, our company’s irrigation area is equipped with three radar level gauges, of the Rosemount 5402 process-sealed series. They are hydrochloric acid, ammonia water, and sodium hydroxide storage tanks. The radar level gauge for the sodium hydroxide tank has been functioning normally, while the level gauge in the ammonia water tank and the hydrochloric acid tank often shows erratic readings. Sometimes it jumps to full scale, sometimes there is no signal; it happens in phases without any pattern, and after some time it returns to normal automatically. Even under normal conditions, the signal strength is very low, with signals of only a few dozen mV or a few hundred mV. The reason I’ve come up with for this is that hydrochloric acid and ammonia are volatile liquids; the vaporized condensate accumulates on the radar antenna, causing interference. I’m asking the experts here if there’s any good solution.