As an Excursion user, you can only have one trip in your account at a time.
Therefore, you must delete a trip before you can add another trip, whether it was created by you or someone else.
When you have a free account and you use a share link to enter a trip that exceeds the limits by too many steps, for example, then it will not be possible to modify this trip.
However, you can see all the information that this trip contains.
If you want to modify this trip, to unlock it, you must take a paid Escape subscription.
You can see the differences between the Excursion and Escape plans on our website: https://www.plan.planningmotion.com/fr/comparer-les-plans-abonnements/