Hello,
The decryption process might take some time. To check the status of your decryption, type
manage-bde -statusto verify that the drive is fully decrypted.
If you are on the Advanced Options screen, select System Restore.
This option takes your PC back earlier point in time.
If this method did not resolve your issue, you can try the Startup Repair method or perform a System Recovery without affecting your Personal files.
That is, on the Windows Recovery Environment Screen, select Troubleshoot > Reset this PC > Keep my files and proceed with local reinstallation.
See if this fixes the issue.