Deleting certain rows with partially duplicate values

Question

If two rows have matching values in column A and in column B, I need to delete the row with the value RED. For example:

A        B        C     D
1    March-1st    2    RED
1    March-1st    3   GREEN
3    March-5th    8   GREEN
6    March-8th    4   GREEN 
2    April-3rd    5    RED
2    April-3rd    0   GREEN

Here I would need to delete row 1 and 5 because they have the value RED in column D while they share values in column A and B with another row.

Here's what I have:

[G,GID] = findgroups(T.A,T.B);
is_red = strcmp(T.D,"RED");
delete_row = false(size(T,1),1);
for ii = 1:numel(GID)
    idx = G == GID{ii};
    if nnz(idx) == 1
        continue
    end
    delete_row(idx & is_red) = true;
end
T(delete_row,:) = []

The error I am receiving says:

Error using tabular/parenDelete Row index exceeds table dimensions. Error in Parser T(delete_row,:) = []