After you file

It depends if you want to change what has been filed and file married, filing jointly, or if you want to continue with filing married, filing separately. 

• Assuming his return was accepted and approved because he used the correct AGI from 2019, there were no errors or omissions, etc, then you can proceed by changing your filing status in the My Info section, entering your details and e-filing also as married, filing separate.
   
• To file married, filing jointly:
  • If his return was rejected, and married filing jointly is preferred, then enter in both his and your details in the tax account that was used last year as if the married, filing separate did not occur. 
  • If his return was accepted and approved, then it will have to be amended as @fanfare stated. For more information, see: How do I amend Married Filing Separately returns to Married Filing Jointly?

For more information, see: Should You and Your Spouse File Taxes Jointly or Separately? - TurboTax Tax Tips & Videos