Hi there!
I am experiencing the same problem. The charge current limit 0A is ignored at SOC 100% when limiting the max sell power. When the max power is raised to a high value so it is not limiting PV power the inverter is discharging the battery immediately (maybe because the battery voltage is overstepping the chage stop voltage at this point).
I found a new firmware (June 23) (just google firmware update deye sun 12k-sg04lp3 eu selber) and gave it a try without further luck with this behaviour. So it seems that this issue is still not resolved in this firmware version (2005-1135-0609)
Do you have any news on this topic?