i run windows 10 on one of the computers, it also has a ‘dial up’ openvpn – started from openvpn gui. it worked fine for a few days but then i started to see repeting

Route: Waiting for TUN/TAP interface to come up...

in the logs and tunnel would not get up for 20-60 seconds. and sometimes even after that the right entries were not added to the routing table.

running those two commands from cmd run as admin fixed it for me [so far]:

netsh winsock reset catalog
netsh int ipv4 reset reset.log

i had to also restart the vpn tunnel