Issue with shipping address?

Hi,
I was wondering if someone can assist me on shipping address on woocomerce. Currently I have zerif lite the website is treeelement.com
The issue in hand is im trying to add a flat rate to medellin which works but I also want another option to bogota flatrate but 10.000 the issue on woocomerce shows the postal code as in colombia we dont use postal code. I was wondering if this was possible?

Thank you