multiple traffic selector to same remote protected resource is not supported. since traffic selector adds the routes automatically multiple traffic selectors to same remote ip can cause issues as you see.
Note: If multiple traffic selectors are configured with the same remote subnetwork and netmask, equal cost routes are added to the routing table. This case is not supported with traffic selectors as the route chosen cannot be predicted.
https://www.juniper.net/documentation/en_US/junos12.1x47/topics/concept/ipsec-vpn-traffic-selector-overlapping-ip-address-understanding.html
Note: If multiple traffic selectors are configured with the same remote subnetwork and netmask, equal cost routes are added to the routing table. This case is not supported with traffic selectors as the route chosen cannot be predicted.
https://www.juniper.net/documentation/en_US/junos12.1x47/topics/concept/ipsec-vpn-traffic-selector-overlapping-ip-address-understanding.html