Predecessors/Successors - How to add without specifying dependancy type

Predecessors/Successors - How to add without specifying dependancy type

I want to add a predecessor without having to specify a specific type (SF/SS/FF/SF) This has obviously been done before in my system, but i am unable to replicate as every value I add automatically saves with SF at the end. How can I add values like I have highllighted in the below :