The web app does not state the minimum shield amount anywhere in the shielding section:
I tried to add another transaction above the minimum to see if it would combine as mentioned at the start of this post: Help with Bitcoin atm buy to wallet
There was no luck. The second transaction arrived on its own and did not combine with the previous one.
The team should add the minimum shield to web app to prevent these issues from arising for others. I’d also like my deposit credited or given back as if the notice was there, I would have ensured it was above the minimum.