I have a question regarding link aggregation

[hjin]

After setting up link aggregation on the Alcatel switch, communication doesn't work when only one port is connected.
However, it operates normally when two ports are connected.
When functioning properly, the connection remains stable even if one port gets disconnected.
Is there a reason why both ports need to be connected immediately after the initial setup of link aggregation?
Is it possible to establish communication by connecting only one port right after the initial link aggregation setup?"

[Gleylancer]

One link is enough to establish a connection, regardless how many ports are in the aggregate.

It's likely that this is a misconfiguration or caused by a bad fiber, if applicable.

[hjin]

I've used the same settings and the same cables.
After setting up link aggregation, when both ports are connected, it operates normally even if both are disconnected and then only one is reconnected. However, if only one port is connected immediately after the initial setup, the port doesn't become active.
Is there any other reason why both ports need to be connected initially for the link aggregation to activate and function properly thereafter?

[Gleylancer]

First thing that comes to mind is a vlan misconfiguration and spanning tree blocking something, but its hard to say without details.