Simlock unlock
How can I unlock simlock on my iphone
iPhone 6s, iOS 15
Question marked as
if you mean that your phone is locked to use only the SIMs of a particular carrier - presumably a carrier different from the carrier you’d prefer to use - see this:
How to unlock your iPhone for use with a different carrier - Apple Support
If you mean that your SIM is locked with a PIN unknown to you, see this:
Use a SIM PIN for your iPhone or iPad - Apple Support