Linton; MCP6200 wouldn’t accept data, invalid floating point value

Hello! I have Linton LT-3268 and LT-2268.
I have entered a data in MCP6200 but it wouldn’t accept 439.200, and I’ve tried looking for solutions in the internet unfortunately they don’t have much of a help.
Does anyone have any information on this on how to fix it?

MCP6200
439.200’ is not a valid floating point value.
