I have a lorawan GPS device which sends data to TTN. With TTN v2 this was working. With TTN v3 I have installed a webhook to cayenne. But in cayenne, the GPS field is empty. Maybe this is because I do not send the data as LPP? Is sending as LPP a must?
Yes, if you have added device as CayenneLPP.
I have not added it as CayenneLPP
then which device have you added?