I own a galaxy s21 ultra 5G device which was bought a year ago in UAE/Dubai. I recently moved to US. Yesterday I bought At&t sim which isn't connecting to 5G. I told the issue to the AT&T and Samsung care, both told me that since the device is bought overseas, the 5G won't work here because bandwidth differs from region to region. They are suggesting me to trade-in with other device.
Hi @itsbkhan09_ That is correct, the S21 ultra you got from Dubai has different chipset and different bands supports. You might be able to connect to 4G and sometimes to 5G in some networks but the performance and connectivity wont be garanteed. The best solution is to switch to a US model. If you dont feel like being stuck with carriers like Att for 2 years, you can buy and trade in your phone from Samsung.com or BBy or any other places. However, I would recommend to get it from Samsung.com as you get a good trade in value, sometimes great offers and you will not be stuck with a carrier phone. Let me know if you have any questions as i am pretty aware of the issue you face when you move from one country to another.
A device bought in the US only works with SIM cards from the US and Puerto Rico. • SM-G998U/U1: USA, Puerto Rico • SM-G998W: Canada • SM-G998N: Korea • SM-G9980: China, Hong Kong, Taiwan • SC-52B: Japan • SM-G998B: All other regions (Even if you enter a network unlock code for your AT&T S21 Ultra, it will not let you use SIM cards from UAE. You can, however, use SIM cards for a different carrier in the US or Puerto Rico.)
This is a common problem with cell phones from other countries if I were you get a phone from the US you will run into meny issues with that phone not being from the usa
