I am looking for suggestions. I can't seem to update one of my Mikrotik hEX S RB760IGS Routers (I'll call problem router). I have 2 of them. One will update without issues. The other one is stuck on firmware 6.47.1. I have a site-to-site vpn between the two routers with DNS servers at each site on the same domain.

At the problem router site, when I try to update (also tried by command line) I get the message "ERROR: connection timed out". When I try to ping mikrotik.com or 159.148.147.196 from the router I get 100% packet loss. I can't even open the website from within the network at that problem location. On the other network I don't have any issues. I tried changing the DNS servers on the router and I get the same results. I can ping all other URLs and IP addresses. For some reason it is only mikrotik.com and159.148.147.196, which gives my the error. I am guessing the update is calling to one of Mikrotik's servers so there are probably more that one, which would error.

There isn't anything between the problem router and my ISP. I think the issue must lie somewhere in the router configuration. I checked and double checked my firewall rules. There shouldn't be anything blocking/dropping it. Nothing shows up under logging. If you have any ideas or suggestions for me to check I would appreciate it.

Thank you,

Your issue may lies in problem of ISP networks interconnection.
Just update it manually: https://wiki.mikrotik.com/wiki/Manual:U ... ing_Winbox
Update board firmware after updating main firmware: System - RouterBOARD - Upgrade.

Manually upgrading the firmware is the easiest solution, however if you want to work out where along the line your connection to Mikrotik's servers is being blocked, run a traceroute.