Activation Lock

Activation Lock is different from Carrier Lock. I’ll assume carrier lock, here.

If Walmart sold the iPhone as a carrier-locked device, you will need to use that carrier, pending plan completion and that carrier (at their discretion) releasing the carrier lock.

If Walmart sold it as a carrier-unlocked device, return it to Walmart for resolution or refund.

Only the carrier holding the lock can remove it. We can’t, and Apple won’t.

How to see if the device is carrier-unlocked:

… How to unlock your iPhone for use with a different carrier - Apple Support

rileyxrose wrote:

I’m sorry what is a “pending plan completion?”

Paying for the full term of the plan associated with any carrier subsidy that was (potentially) included with the iPhone.

A carrier-locked iPhone will usually have some form of subsidy included, and the carrier may or may not choose to unlock at the completion of the contract term. Some carriers will unlock. Some will not.

If Walmart sold the iPhone as unlocked and with no subsidy, well, it’s not unlocked. Contact Walmart.

Your carrier is the company that you pay for cellular service. When you sign up with a carrier, you commit to a " service plan agreement". That might be 12 months, 24 months, 36 months, etc.

When you have completed the "plan" and have no outstanding balances, you should have an option to have the lock on your phone to your current carrier removed, so you can contact another carrier and set up service with them if you are not happy with the current carrier.

The details are in the "fine print" of the agreement with your carrier. Expect a hassle if you want to change carriers.

If you bought it from Walmart the carrier is probably Straight Talk.