My apols Dr C,
I must have missed it... :-[
In my relatively limited experience with the Lelit, every one I have benchtested has been very tight and they are harder than others I have seen.
We have replacement Lelit group seals for sale, but they are one size fits all so I fear you will have to be patient as yours wears in. It might be possible be to remove the seal and give the other side a gentle rub down with some wet and dry or similar.
Another option is to slightly decrease the thickness of the group handle lugs by grinding them down slightly.
Perhaps some other owners might be able to offer suggestions.