Your pup has hit that lovely, boundary pushing adolescence we all know and love! We also went from a great recall to no recall with Maddie around that age. We used a long line (30ft) - a friend managed to find a nice light one with a small clip so that it wasn't too heavy from her collar. We also worked on finding a toy that she would focus on. For her it was a golf ball. Luckily she didn't ever want to catch it (I dread to think what that would do to her teeth
) but would chase after it and bring it back. We usually took 3 balls out with us, so when she'd got one we had others to tempt her back with. Eventually we graduated onto a chukka-ball, which is 2 golf ball size tennis balls (if that makes sense?) on a bungee rope. She loves this toy so much that it doesn't matter where we are - if the toy is there she stays completely focussed. :rah:
It took us a long time to get to the point where we trust her off lead (and I never would around cars/ roads even now), probably 9 - 12 months of long line training, but it was completely worth it.
The other thing I did was whistle train the re-call, so that she didn't react to the tone of voice (happy, panicked, anxious, angry, irritated etc.) but to the command. That has worked fairly well with her, but brilliantly with Pippin. And we used plenty of treats as rewards, usually saving something really good for when we're out and about that she doesn't get any other time.
Also, having got an ok recall, we don't take it for granted. She's 4 yrs old now, and still has the potential to have selective deafness
so I reinforce the recall, going back to some basic training, just to remind her that I am a fun person to be with! Much more fun than all those smells, squirrels, rabbits etc.