Is the amount sent/issued by the IRS the same as the refund amount shown on your federal tax return Form 1040 Line 35a? - https://www.irs.gov/refunds
If not, then go to this IRS website for information on reduced refunds - https://www.irs.gov/taxtopics/tc203
Are you also receiving a state tax refund? If so, the state refund is sent directly to you based on how you chose to receive the state tax refund, it does not go through the third party processor.
Use this TurboTax support FAQ to check the state tax refund status - https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund
Have you factored in the TurboTax account fees and the TPG service charge of $40 plus any applicable sales tax?
Review your TurboTax account fees -
Sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the bottom of the screen and on the section Your tax returns & documents click on View Order Details
If you requested to have the TurboTax account fees deducted from your federal tax refund, the IRS will send the refund to a third party processor to have the fees and the service charge deducted. The third party processor will deduct the TurboTax fees plus the service charge and then attempt to direct deposit the remaining refund balance into the account that you entered on your tax return.
For the status of your tax refund you will need to contact the third party processor, Santa Barbara Tax Product Group, using their website - https://www.sbtpg.com/
Tax Products Group Contact Information - https://help.sbtpg.com/hc/en-us/articles/230084587-Contact-Information
Call 1-877-908-7228
Or - TPG-CSsupport@greendotcorp.com
Remember that your state refund comes separately and is not part of the refund from the third party bank. Did you remember to do the math and subtract your fees and the extra refund processing fee from the amount sent to you by the third party bank?
How can I see my TurboTax fees?
https://ttlc.intuit.com/questions/2565973-how-do-i-review-my-fees-in-turbotax-online
If you have taken all of that under consideration, check the IRS refund site to see if the IRS issued the refund amount you expected. If your refund is still "short" contact the third party bank.
Santa Barbara Tax Products Group, LLC (SBTPG) is the bank that handles the Refund Processing Service when you choose to have your TurboTax fees deducted from your refund. This option also has an additional charge from the bank that processes the transaction.
You can contact them SBTPG, toll-free, at 1-877-908-7228 or go to their secure website www.sbtpg.com
https://ttlc.intuit.com/questions/2580357-who-provides-the-refund-processing-service