Thanks for your remark. I forgot to check the Approval field on RITM level.

You are right and I checked that with sequential approval, something is changing it back from Approved to Requested to keep the 2nd approval running. 

This is rather odd. 

I'd rather prefer not to use flow designer as the logic should be handled by a team who is working in Catalog builder and the interface intuitively allows you to group approvals which would indicate me a parallel logic.

I raised my ticket also with support as we need to get this working so I'll see if they come with an idea.