My iPhone 12 Pro Max is not displaying 5G

Then what it is displaying instead, 4G, LTE, something else? Does your carrier and your plan support 5G? If so, sounds normal to me and it just means that 5G is not supported in your location and that your iPhone is using a different one of your carrier’s networks.

Olamilekan05 wrote:

Please what can I do to make my iPhone 12promax to support 5g

You need to actually read my advice above instead of just repeating your question. Your iPhone does support 5G, but its availability also depends on your carrier, plan and location.