For a complete do-over, I would do the following:
1- Delete the device in the app (if it shows up), including any related child light/device created
2- Delete all DTH’s and related handlers for this fan/light - Any of them if you installed mutiple versions
3- Clear the Smarthing app’s cache/data:
Iphone - https://www.wikihow.com/Delete-Application-Data-in-iOS
Android - https://www.cashify.in/how-to-clear-app-data-and-cache-on-android
4- Go into the smartthings app, click the + to add a device, click “device”. Click “scan nearby”. Quickly move to the next step while it is searching
5- Factory reset the ceiling fan controller to re-pair it - turn off your fan for 3 seconds, then turn it back on for 3 seconds. Repeat these steps 5 times. The light will blink 3 times when factory reset is successful. It should then connect
6- It should install as some sort of generic device. Obtain the latest DTH’s from this link and install both the fan and child device- https://github.com/rafaelborja/SmartthingsKingOfFansZigbee/tree/master/devicetypes/rafaelborja If unsure follow this guide - FAQ: An Overview of Using Custom Code in SmartThings (SmartThings Classic)
7- Assign the custom handler to the fan in the IDE
Hopefully that should get you running again.