From the C50 device page provided by @LilRedDog , you should eventually find this old post with instructions for how to construct a recovery file to help you unbrick your C50 v4 using TFTP.
It does contain a link to a prebuilt TPLink recovery file for C50 v4 EU version.
https://forum.openwrt.org/t/restoring-stock-firmware-for-archer-c50-v4/63773/9