Rashford still hasn't extended his contract with Manchester United and it must be getting more worrying for the team on one hand. Because Rashford has made a huge progress recently. Under Erik ten Hag's management he has improved his performance a lot. He has made a huge level of contribution to the team with goals and assists throughout the season.
But his contract is still ending by the end of next season. This can even encourage some top teams to make an offer for him this summer. I wouldn't expect Manchester United to sell him of course but I wonder if Rashford would think of it.
Ten Hag already stated that he wants Rashford to stay and Rashford must extend his contract soon. So, we don't need to be worried about Rashford's future because he is likely to stay in Man United longer. We also never heard an issue about any top club that wants to negotiate seriously for signing Rashford, this is a sign that there is still no offer from other clubs. It indicates that Rashford is still focused on negotiating his contract with Man United. Rashford also must prefer to stay because he is a real product of Man United academy, he should feel Man United is like his own home. He seems to have no intention to leave Man United in the near future.