My South African ISP is telling me to upgrade to version Archer C20(EU)_V4_181213 but when I go to the South African TP-Link website it only shows me the version that I have. I found the version that...

I have the same problem in South Africa. My ISP wants me to upgrade my firmware to Archer C20(EU)_V4_181213 and I managed to get it on the Global site but it comes up with an error 4503. The ISP...