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unfortunately there is not a lot else you can try at home as this symptom generally indicated a failure within the top system (drive unit, sensor, control unit)
as for what you can try, you can unhook the car battery for an hour to preform a full reset, and you can check for any blown fuses
aside from this, the issue will not be fixable at home, without proper diagnostics, and without replacement parts
in order to get the top up, you can use the manual over ride as outlined in your owners manual, for your convenience I have uploaded the process at this link: CLICK HERE
sorry to have potentially bad news, please don't shoot the messenger - I can only give the honest answer, which I have done. Please remember that a low rating PUNISHES me for my honest answer, and I receive nothing for my time and answer until a positive rating is clicked
Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.