To reproduce it we need 2 commits for the same route.
```
set protocols static route6 ::/0 next-hop fe80::11
commit
set protocols static route6 ::/0 next-hop fe80::11 interface eth0
commit
```
Check routes:
```
vyos@r4-1.3# vtysh -c "show run | include ipv"
ipv6 route ::/0 fe80::11 eth0
ipv6 route ::/0 fe80::11
[edit]
```
Delete all protocols, expected behavior delete all routes
```
vyos@r4-1.3# delete protocols
[edit]
vyos@r4-1.3# commit
[edit]
vyos@r4-1.3# vtysh -c "show run | include ipv"
ipv6 route ::/0 fe80::11
[edit]
```