@Marie299 - you want to move forward, quite rightly. Well done for asking for advice. In basic terms, treat your daughter as another person that you are interested in, ask her questions, listen.
What do you know about her already?
What are her interests? Link to these.
What do you regularly and consistently do now?
Do you write every week, consistently so that your daughter expects contact?
What else do you already do that is working well? Build on it.
Some longer term steps.
Start with understanding
Accept how the child feels, even if it’s sad or hard to hear. She might feel angry, scared, or unsure. Don’t rush her or push for contact. Learn about her life now—what she likes, her friends, what she does every day. Try to understand who she is today.
Begin with small, gentle contact
If she doesn’t want to see you yet, try simple ways to keep in touch.
Send short letters or cards that are kind and easy to read.
Talk about small things you remember or things you’re doing that she might like to hear about.
Don’t say anything that makes her feel guilty or pressured.
You could also send a short video or voice message, if the grandparents agree. Always keep messages friendly and about her, not about missing her.
Work with her grandparents (and social worker-do school have Early Help/family workers?)
Be kind and respectful to the grandparents. They are caring for her now.
Talk to them and the social worker about how to start contact again.
Follow their advice.
Ask for help from family workers or people who help children and parents rebuild relationships.
When she’s ready, meet in small steps
If she agrees to meet, start slowly.
Meet for a short time in a safe, calm place like a park.
Do something together, like drawing, feeding ducks, or playing a game.
Keep things relaxed.
Always end the visit in a positive way so she feels good.
After each meeting, talk with the social worker/grandparents about how it went and what to do next.
Be reliable and calm
Show her you can be trusted.
Keep your promises.
Be calm and kind, even if things are difficult.
Don’t talk about grown-up problems with her.
Over time, she will start to trust you again if you stay consistent and caring.
Look after yourself too
It can be hard to rebuild contact.
Get support if you need it—talk to someone you trust, join a parent support group, or ask for help from a counsellor.
Learn about ways to connect with children who have had time apart, like using play and gentle curiosity.
Focus on her needs and feelings, not your guilt or sadness.
Hope this helps. Good luck with the time and effort you will need to put in.