Tado target temperature via setpoint throws cast error

Maybe? this is a problem with the binding?

See: Tado Binding doesn't accept command via REST - #10 by rlkoshak
Also: openhab2-addons/addons/binding/org.openhab.binding.tado/src/main/java/org/openhab/binding/tado/internal/handler/TadoZoneHandler.java at 928db7e3e9102f848995b3a8e8215c11c6f947af · openhab/openhab2-addons · GitHub

Which OH2 release are you running @Haves ?