Thanks for confirming!
The Samsung S21 Ultra has been very popular and high in demand. As a result of that, certain versions of the phone are currently on backorder.
Did you order the 128GB or the 256GB?
If it was the 128GB, the delays are currently about 1-2 weeks to get the phone. For the 256GB, it can take 3-4 weeks.
I hope that info helps out