There can be several reasons that your refund has increased.  The most probable is that you qualified for one of the tax credits.

If you look on your tax return FORM 1040 you can check these entries.

• Line 19 Child Tax Credit
• Line 27 Earned Income Credit
• Line 28 Additional Tax Child Tax Credit
• Line 29 American Opportunity Credit (For College)
• Line 30 Recovery Rebate Credit
• You also may have had more taxes withheld on your income.

.....and if you received either of the Stimulus payments, but have not reached that part of the interview yet .... your refund may already be including one or more stimulus payments you may not be eligible for....when you enter the stimulus you've already received (if you've received any) ...the refund will go down significantly