Usually it's either hungry, diaper wet or stomach ache. Could be baby wants a sense of security, likes to be swaddled. At times my baby will cry when she is unable or hasn't burp after milk, she will stop crying after I burp her. My baby will struggle when her father carries her at times because she is not comfortable. Once I take over, she is alright.
Could it be colic if your baby is still young?
Vanessa