Solved

Health didn't increase after I used tokens to fully heal my driver before the race.

What did you try to do?
I tried to finish the race, thinking it will automatically heal after the race. I tried refreshing, etc. I tried logging in PC, it still happens.

What happened instead?
Nothing happened

Did the problem happen while using wi-fi, mobile data, or both?
Wi-fi

Did the bug happen in the app, on PC, or both?
Both

What is the model of your device?
Samsung A20s

What is the operating system?
Android

What is the version number of the operating system?
Android 10

What operating system is your PC?
Windows 8

Which browser did you experience the problem in?
Chrome

Can the bug be reproduced?
If I can't spend tokens, nope. Since it's in the token bug.

Additional comments:

Hello Skylark 

Checking your account history, what I see is that you tried to heal your driver at 11:51 am , when everything was locked by then. Having said that, obviously being on the training page, the server only half recorded the process, deducting the tokens, but not healing your driver. I have returned the tokens spent on healing. Please try to run this process a few minutes earlier in the future to avoid what happened to you.

I wish you a Happy New Year.
Best Regards