Why would my 2020 balance shows as unavailable on IRS website

Per IRS, they have around 12 million tax returns that have been caught in a processing backlog created by the pandemic, which shut down the IRS for a time. Americans should see their refunds in the coming months. "We would hope to be through this backlog by the summer," said IRS Commissioner Charles Rettig.

• The IRS also has millions of returns that have to be manually verified which is also causing a delay.
•  Keep checking the IRS Where's My Refund page to see if your refund status has been updated.

Other reasons some returns take longer to process are the following: 

• Perhaps you had a refund offset.
• Includes errors
• Is incomplete
• Is affected by identity theft or fraud
• Includes a claim filed for an Earned Income Tax Credit or an Additional Child Tax Credit. See Q&A below.
• Includes a Form 8379, which could take up to 14 weeks to process
• Needs further review in general
• The IRS will contact you by mail when we need more information to process your return.