Can I disable margin trading on my account?

Yes. Margin can be disabled

1. Click on the Invest tab
2. Select the Individual Active SoFi Invest account
3. Click the More button (web) or gear icon (app)
   
   • Web:
     
     
   • App:
     
4. Select Margin Investing
   
   • Web:
     
     
   • App:
     
5. Click the box next to Yes, enable margin investing to uncheck the box and turn off the feature (web), or toggle off the Margin investing enabled option (app)
   
   • Web:
     
     
   • App:
     

Note, however, that you cannot disable margin trading if you have a pending margin debit balance.