Also, get a longer long lead and attach it to a harness on her back. Do fetch with a ball rolled very slowly rather than something that makes her bolt to the end of her like lead.
Enforce recall by calling her back with a very high value treat. If she doesn’t, then use gentle lead pressure to lure her in.
Practice makes perfect and you’ll have to do many reps.
Start the fetch maybe with a ball rolled very slowly 1 or 2 metres away max then build from there.