Hi
You have to make sure that the Flow itself is properly shared to YOU, and that all the Connections being used are also shared properly.
But right now you don't have permission to activate it due to that connection.
And you may need to create another.
Here is how you do that. (And really you should be using Connection references, not connections.
Anyway
Open the Flow
Go to the Action that has a Connection associated (for instance your SQL One)
Click on the ... on the Header of that action
Near the bottom in the popup, it will tell you what connection OR connection reference it is using
It will also have an option to create a new connection. Thats' how you would replace it.
another option is to create the Connections and Connection References BEFORE you click the ...
If you make them and already have the flow opened, once you create them do a CTRL F5 first before trying to change the flow
Then do the same thing. Click the ... on the header, but NOW it will show your new connection/or reference and you can simply select it.