Hey Susan! We're super bummed to hear that you got unexpected results!
Since silver is basically a mix of all primary colors, the final result is heavily dependent on the starting hair color. A neutral platinum base is your best bet for a true silver - hair that's cool-toned can lead to blue strands, and hair that's too warm can lead to green strands.
What you can do is use a little Pastel Red Daily Conditioner to help cancel out the green tones, making your hair a silvery shade. Definitely do a strand test on a piece of your green hair to make sure it doesn't absorb more pigment than you need.
All of that being said, our Color Consultants have reached out to you to chat more - keep an eye out for their email!