PJiang, after reading your "移民局 Online Status 释义", I found there is a Receipt Number for my I-130 (F2A category) on the back of my cancelled check, which is XXX-XX-XXX-XX377. However, when I got the formal I-797C, the number on it is XXX-XX-XXX-XX378. Everything else is correct. On the USCIS.gov website, only XXX-XX-XXX-XX378 is valid, but not XXX-XX-XXX-XX377. How could this happen? Will it introduce troubles to my petition later? Thanks a lot for your time!