Hey Andyandy seems its seem quite some time(about 4 months since the letter was sent), are you in the US (if so did you change your address and can you get the mail from the old address if you have). When you call USCIS did you try calling both Vermont and California? I would also get my senator or congressmen involved at this time. Its very possible that your waiver has been approved but you aren't receiving the mail. goodluck
OVO got a reaction from Andyandy in 2018 J1 WAIVER TIMELINE