We just arrived in US lst May 10, 2022 under immigrant visa, but there is no entry stamp on our passports. What do we need to do? Will this cause problem in generating SSN and GC? Thank you!
Even if you were admitted correctly (in which case your I-94 will not show up at all since you're a LPR), you may still want to go to the CBP office to get a stamp. The stamped visa becomes your evidence of permanent residency in the US until the actual green card arrives, so the stamp is pretty important.
From the CBP FAQ:
What should a traveler do if he or she was admitted incorrectly to the United States?
If a traveler was admitted incorrectly to the United States, the traveler should visit a local CBP Deferred Inspection Site to have his or her admission corrected. A list of Deferred Inspection Sites can be found on CBP's website, https://www.cbp.gov, under the "Ports" link at the bottom of the page. If a traveler was issued an incorrect I-94 by United States Citizenship and Immigration Services (USCIS), the traveler should refer to the Form I-102, which can be found at https://www.uscis.gov/forms.