CMOS Problems

You can't replace the CMOS chip itself without replacing the system board. 

Most newer models do not have separate CMOS batteries - they tap the main battery for that purpose.  What model XPS do you have (7590, 9350, etc.)?  And is the main battery in good condition or is it running low on battery runtime?

@ejn63​ Thanks for responding. The battery is new and original. I bought it thinking it would solve the problem.
The computer model is: XPS 13 7390 2-in-1
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Does the system see the battery in setup (F2 at powerup)?

@ejn63​ When you turn on your computer, this screen always appears:

It tells me that the client has to turn the computer off and on again so that it can start Windows properly.

This other screen almost always appears. (I downloaded this photo from the Internet, but the message is the same)

You need your bitlocker key -- if you activated the system with a Microsoft account, log in there are you can retrieve the key.

If you did not activate with a Microsoft account, but did back up the key ahead of time, you'll need that backup now.

If you did not back up the recovery key, you will need to do a ground-up reinstall of Windows on the system.  

The other issue is a separate one -- if the battery in the system is recognized but the system is not retaining its CMOS settings, it's likely the mainboard needs to be replaced.

@ejn63​ Thanks again for responding. I have the BitLocker password and entered it, and it worked, but the problem persists. When the computer shuts down, the screen appears again, asking for the password, and so on.
In Windows 11, the battery appears to be working perfectly, charged, and works without being plugged into power. Are you sure the motherboard needs replacing?

With the system disconnected, try unplugging the main battery and holding the power button for 30 sec.  Reassemble and test again.

If the system senses the battery and runs OK from it, but the CMOS settings are not retained when power (AC) is disconnected, it sounds like a problem on the power rail supplying the CMOS chip.  It's your call whether to see if a repair shop can fix the existing board, but the cost will be similar to a board replacement even if they can.