I understand you have a 2019 XT1200ZE.
The procedure is simply to page through the function display using the menu switch. Only the grip warmer, info display & damping force are available functions when riding - the preload adjustment will only appear when the bike is stopped with the engine running, best without any load on the bike to give the servo a chance. I assume the dash is reporting that you are in neutral & you have no ES warning light. It is possible to overheat the preload servo, but the system should always reboot itself once it cools down after around 6 minutes.
If preload still isn't showing for some reason, then it will be a trip to your dealer to check for codes, as late model bikes require an OBD reader.