IRS Did not send $1400 stimulus as part of refund submitted with Turbotax

My daughter received a letter from the government that she was still eligible to receive the 3rd stimulus of $1400.  She is single and lives out on her own at a minimum wage job.  I helped her do her taxes on my computer using the Turbotax Home & Business version I purchased from Costco.  Her taxes were very straight forward and Turbotax entered all the info about the stimulus money.  When she filed online Turbotax said she would receive $1906 from the IRS but instead her electronic check was only $506 so minus the $1400 stimulus money she was expecting.  Her tax return was accepted by the IRS but they ignored sending the stimulus portion included with the return.  What happened and how do we fix that?