Thanks for posting here, @Amolesh.

Joining the thread to share some insights about this Import custom form styles option in QuickBooks Online.

Reading through your previous post, it looks like you are just trying to enable this feature. From the information we got from our Notifications Team, any company files who did not enable Import Styles from QBLabs on or before 6/24/2021 will no longer be able to activate it.

Any existing QBO companies who enabled this feature before the said date are currently not affected and will continue to have access. The Import Styles feature was disabled for newly created companies, and there are plans to completely remove this from all QBO companies in the future.

Otherwise, if you have this option enabled before and it had stopped working, you can continue working with our Support Team. They can check on this and create an investigation for a fix.

To get a hold of a representative to check your account, follow these steps:

1. Go to the Help menu then choose the Search tab.
2. At the bottom click on Contact us.
   
3. Enter the keyword Account Management and Billing in the What can we help you with? box.
4. On the next screen, scroll down to How would you like to connect with us section.
5. Choose Chat with us to initiate a discussion with a live agent.
6. Enter you account contact information then press Get a chat. When using this option, make sure to enable pop-up windows. The chat box will appear at the bottom right section of your monitor, and an agent will be with you shortly after. See this:

Post here again for any QuickBooks questions besides this template import concern. I want to ensure you're taken care of, and I'm here to provide further assistance if you need any. Have a great day!