Some router manufacturers may choose to limit the auto-channel selection feature to channels 1 through 11 to ensure compatibility and compliance with regulatory requirements across different regions.

Is TP-link such manufacturer? 

I live in an area where I can legally use channels from 1 to 13. My router supports the same range. Yet, if I select AUTO under 2,4GHz network it never jumps on 13th channel, and it always stays within 1-11 range. Furthermore, all neighbors are on 1-11 channels where it gets very crowded and there is absolutely no one at channel 12, 13. 

I checked it numerous times on numerous spots with numerous devices and conducted numerous tests and channels 12, 13 are never used, nor by others, nor by AUTO mode of my Archer AXE75 routers

Any insights on this?