Connecting lines on combo bucket

[Senior Citizen]

Sorry if this is a dumb question but I have a CAT 226B skid steer and have just bought a combo bucket from quick attach. I have the bucket on the machine but am having trouble getting the lines connected. The smaller line I finally got connected but the larger line just will not go on no matter how hard I push. Anyone tell me what I am doing wrong please?

 

[Tazza]

I have had a new set of couplers that were really tight. Its possible that its just new or there is pressure stuck in the lines. Can you crack the lines to the couplers to make sure there is no pressure behind it to stop it going on?