From the get interface it's clear that it's failing at L3 connectivity, l2 is fine port is up, most probably track-ip is failing.
link down, phy-link up/full-duplex, admin status up
status change:23, last change:05/24/1997 00:05:56
Can you check the flow basic for the trac-ip on both the devices when it's working and when it's not working. This will show you the working track-ip path and if there is any issue then where the trac-ip traffic is failing.
https://kb.juniper.net/InfoCenter/index?page=content&id=KB12208&actp=METADATA
Thanks,
Vikas