Line 18 Record cannot include more than 4 comma-separated fields (ad system domain, publisher account ID, relationship, optional - certification authority ID)
Line 25 Ad system domain mediabong.com is not a known exchange domain. Ensure the spelling is correct, check the partner documentation, or have the partner update the IAB Tech Lab normalization mappings: https://wiki.iabtechlab.com/index.php?title=Ads.txt_Normalization_Mappings
Line 29 adnxs.com is not the canonical exchange domain. Use appnexus.com instead.
Line 30 adnxs.com is not the canonical exchange domain. Use appnexus.com instead.