I am currently on the Ideen Expo 2019 in Germany and only have one Arduino Nano with me. For my experiment to work I need to connect +5V to the VIN Slot on the Arduino via a power supply and I accidently plugged a 9v supply in there. After that, some of the digital Pins didnt work anymore so I used the other ones (and I could still upload sketches and the program on there worked fine). But today I cant even upload anything, the L led just blinks seven times and nothing happens, not even the program on there works. I also have no output at all and when I want to upload anything, I get the avrdude stk500_getsync() error. Is there any way to recover from this or is it finally dead?