Scam call.  Related to all the others I've gotten from the same prefix since April '16 to current:
408-306-3481
408-306-3183
408-306-3362
408-306-4246
408-306-7606
408-306-2348
408-306-9574
408-306-5234
All the above call and don't leave messages and I never pick these calls up.  They come in and I block them.

This number and others stated above are fishing for numbers that are no longer in use.

Add to this list these numbers just append them to 408-306-
2186
1490
8742
2286