ECAM22.110.B Empty tank error message

Hello everyone, I
have yesterday our Magnifica S ECAM22.110.B back in operation, which was stored due to relocation, etc. a few years and was not used (we bought it back in 2013) It
took

a bit, but it runs again and the coffee is also good, that reassures me already. However, it does not recognize correctly when the tank runs empty, which is why, for example, the descaling program aborts (I have then simply "manually" descaled, so alternately from the hot water nozzle and from the coffee outlet let out - also worked). The triangle and coffee grounds then flash and the light for water lights up continuously. According to the manual, this is the error for "coffee grind too fine", but as I said, it always appears when the water tank runs empty and has nothing to do with the coffee, which is fine.

It is not an acute problem now, because you can use the machine as it is, it just wonders me and I wonder if it can be (easily) fixed?

Thank you very much for your help and have a nice Sunday
Best regards, plumquake