An administrator has restricted sign in.To sign in make sure your device is connected to the internet and have your administrator sign in first

Hi MrPrasanth1

I am Dave, I will help you with this.

That notification should only show when someone remotely locks the device using the 'Find My Device' option when a device is stolen.

Did you ever lock that device remotely?

Same issue here.

Apparently I have linked this user with the microsoft account. I then use only pin code as login method.

Then I might have locked the device and delete it from the microsoft account.

Now the logon is asking for ...

An administrator has restricted sign in. To sign in, make sure your device is connected to the Internet, and have your administrator sign in first

after i enter the correct pin code.

Yes , but I thought it will be opened later through the Microsoft account by unlocking the system.

Hi, my name is Anderson Souza, I hope I can help you with your issue.

As you are unable to log into your computer system, you can use this method to access the recovery environment and do a Windows Startup Repair: 

1 - Turn on your PC. 

2 - As soon as the Windows logo appears on the screen, press and hold the power button. (This will immediately interrupt the boot sequence.) 

3 - Repeat steps 1 and 2 two more times. 

After the third interruption, Windows 10 will open in the Advanced Startup environment, and then you can continue with the steps below to use the startup repair tool to fix startup problems with Windows 10. 

Using Startup Repair to fix loading problems 

While in the advanced boot environment, use the following steps to use Startup Repair: 

1 - Click the Troubleshooting button. 

2 - Click the Advanced Options button. 

3 - Click the Startup repair button. 

4 - Select your account (if asked). 

5 - Enter your account password (if asked). 

6 - Click the Continue button. 

A quick tip: If your computer is charging properly, using this tool, you will receive the message "Start Repair could not repair your PC" because there is nothing that needs to be repaired. 

Once the steps are complete, the Start Repair feature will proceed to scan, detect and correct any problems that may prevent the device from loading properly. 

In addition, the repair process creates a SrtTrail.txt file in the "C:\Windows\System32\Logfiles" folder with log information that you can view for a better understanding of diagnostics.

I. Did accidentally lock a laptop on my network and have trawled the net trying everything that was suggested.

In the end, I removed my hard drive formatted then reloaded every thing from my cloud back up.

All is working now except I still sometimes get this pc is locked, however it still opens with my password.

I have to say Windows help was useless.