Your phone might support using an eSIM (embedded SIM card), in addition to the physical SIM card. Contact your carrier for details.
Your phone supports an optional microSD card up to 1 TB.
A Class 2, 4, or 6 card is sufficient.
Your phone uses the card as portable storage for media files: photos, videos, and music. Because it's portable, you can easily swap the card and its content between devices. After you insert the card, be sure to update settings within media apps (like camera, music, and podcast apps), so they use the card to store content you create or download.
You can't store apps on the SD card because it is portable storage.
If your carrier provided you with an eSIM:
Insert the SIM tool into the tray hole and gently push to pop it out.

Insert or remove the cards as needed.
To use an SD card and a SIM card:

Or, to use two physical SIM cards (not available on all models):

To see if your phone supports two physical SIM cards, go to Settings > About phone > Device details. If you see SIM status (sim slot 1) and SIM status (sim slot 2), then you can use two physical SIMs in your phone.
Push the tray back into the phone.

You may need to erase your eSIM:
When you erase an eSIM, you remove the following capabilities from the phone:
Erasing the eSIM does not cancel your mobile data services. To cancel your services, contact your carrier.
To erase an eSIM:
To restore an eSIM you erased, contact your carrier.
What type of issue do you have?