At a loss

How can I sleep train my baby. She will only sleep on me. I put her in her crib and it's like she fights sleep all night long, when I carry her, she sleeps perfect. I end up carrying her cz I'm a working mom and we both need sleep. She's four months old. No judgements, just some advice. Please help.

Update 1: Thanks y'all for the advice, I've started letting her cry it out which is really hard😭😭😭. I did it last night and she cried for a good 40 mins. She finally fell asleep but kept fighting it. I used the pacifier which helped. I'm going to keep trying and hopefully she'll get used. The problem however is I work alternating schedules i.e. sometimes I work 3-11.30pm so I'm hoping her father will be able to continue the training when I'm at work. Wish me luck ladies. This is not easy at all.