Hi, I am Dhanam, Independent Advisor here to work with you on this issue.
I know this has been difficult for you, Rest assured, I'm going to do my best to help you.
Select Start > Settings > Personalization .
Select Colors and scroll to Accent color.
Turn on Show accent color on Start and taskbar. This will change the color of your taskbar to the color of your overall theme.
Note: This option is only available if you select Dark or Custom as your Windows color (under Choose your mode). If you choose Custom, you'll also need to choose Dark for Choose your default Windows mode.
Refer this also:
https://support.microsoft.com/en-us/windows/how....
This is a public user-to-user support forum. I'm a user like you helping other users. I do not work for Microsoft and cannot access any user accounts.
I hope this can help you. If this still can't solve your problem, just let me know and I'll do my best to try to help you.
Regards,
Dhanam,
Independent Advisor.