It sounds like you're trying to create a process or action button to disconnect several leads from a sequence in the Leads view. Your approach of flagging the leads and then using a process to disconnect them should work, but it's possible that there's an issue with your current process.
Here's a suggested approach to creating the process:
1. Start by creating a custom Yes/No field on the Lead entity, named something like "Disconnect from Sequence".
2. Add the new field to the Leads view so that you can easily select multiple leads and update their Disconnect from Sequence field.
3. Create a new on-demand process in the Power Automate or Dynamics 365 environment that is triggered by a selected record(s) in the Leads view.
4. In the process, add a "List records" action to retrieve all the selected leads with the "Disconnect from Sequence" field set to "Yes".
5. Add a "Apply to each" action to loop through each selected lead.
6. Within the loop, add a "Check conditions" action to check if the lead is currently in a sequence. You can do this by checking if the lead has any related records of the "List" entity, where the "Type" field is equal to "Marketing List".
7. If the lead is currently in a sequence, add a "Remove from marketing list" action to remove them from the sequence.
8. Update the "Disconnect from Sequence" field for the lead to "No" to indicate that they have been disconnected.
9. Save and activate the process.
Once you've completed these steps, you should be able to select multiple leads in the Leads view, flag them with the "Disconnect from Sequence" field, and then use the new process to disconnect them from any sequences that they're currently in.
