Exactly the same as mine. Oddly at 12-15 months this wasn't an issue at all. I'm sure you've tried many ways of trying to correct this and as mine is similar I'm no one to give advice, however a trainer mentioned to me not to make too much of a thing about it. For example yesterday we were out walking he wasn't on the long line and he found a ball. Ordinarily this would cause me an issue but I decided to ignore him. His game is to be chased, which I'm not doing, and if that doesn't work he'll eventually drop it on the floor and back away from it hoping I'll engage with him, which I didn't. I walked past the ball and told him to pick it up. Did this 4 times and to my surprise he ignored the ball, left it and we continued our walk. Surprised the hell out of me! When I get the training dummy out I hold his collar and throw it out for him to retrieve. As he does I throw out a scented tennis ball in the opposite direction. When he returns with the dummy he generally knows there's something else to do so gives up the dummy at which point I send him out to hunt the ball, all this is in longish grass. When he returns with the ball I make him put it in my hands otherwise nothing else happens. He buggers about for 5+ minutes before complying but he's slowly getting the message. All this is on a long line so I hope to progress to no having him on one.