I use as an entry source Salesforce Data. In case i want to target leads, i choose Lead ID everything works properly. Now, i want a journey for Accounts that i have in Salescloud.I tried everything but nothing worked.
You cannot target business accounts, so you can utilise the fact that every PersonAccount in Sales/Service Cloud has a Contact record associated with it. This Contact is linked via "Person Contact ID (Contact)", which needs to be used in the "Who do you want to inject?" step.
If you like to trigger the Journey for Business accounts you can only select fields containing a User-ID.