Deflated tyre

the low tyre pressure indicator came on in the panel. I chacked all pressures & found one of the front tyre was low. I pumped the tyre to it's correct pressure & rechecked it after a fow days & it did not deflate.The tyres are now all at the correct pressure yet I am unable to reset the run flat indicator in the panel. The only thing I can think of is. Do I have to remove the wheel & then refit. I have done everything else. thanking you