Track and conferm USPS

Bought a signal light switch on April 21 USPS received it the 23 I have been tracking it everyday and no other updates as to were it is.Anyone know why the USPS is so slow to update me as to were it is in transect .I got the part from Old car parts.here is my tracking number lj861412205us maybe someone hare knows how to search were it is lol.Thankssss.