Hi everyone, I know there is possibly no one around here from T-Mobile US. Maybe someone has a contact to T-Mobile US that can possibly have a look into this? I've tried some official e-mail address from whois information months ago but no response. We are AS198288 and our prefix 5.34.248.0/21 has only limited reachability from / to T-Mobile US (mobile / hotspots users and t-mobile website / e-mail). It's no routing issue I guess as traceroutes / ping work. I was in the US a week ago and also had a T-Mobile 4G contract phone. Same issue, ICMP works, TCP / UDP gets blocked to 5.34.248.0/21. I actually think there are some legacy filters in place, maybe they used 5.0.0.0/8 as "private addresses" in the past. Anyone with an idea or a contact to T-Mobile welcome. Thank you very much. best regards Marco