It is part of the bridge, and internet is supposed to be connected to ether1 in the default configuration, a recent thread where the ports were swapped, as reference:
Routing internet from SFP to ethernet ports (RB5009UG)
that case is for when the router is directly attached to the fiber, so there is a VLAN on top of the sfp-sfpplus1, but the general ideas are the same, basically:
- remove the sfp-sfpplus1 port from bridge
- categorize it as WAN
- add a dhcp client to it
- add (optionally) the ether1 to bridge together with the other ports
- remove the categorization as WAN for ether1
Usual generic recommendations (hopefully useful for a new user):
The twelve Rules of Mikrotik Club
GP & CSA (Good Practice and Common Sense Advice) for Mikrotik devices