It is not possible to breed Axolotls.

I was able to breed an Axolotl with Tropical Fish it just takes time.

https://bugs.mojang.com/browse/MC-208644?focusedCommentId=864437&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-864437
Please what?

look at the changelog:
"Axolotls currently love tropical fish, though this may change. Tropical fish or tropical fish buckets can be used to mate axolotls"

I am unable to reproduce this issue. It just takes time for them to breed.

I found out that it works, and i just had the particles set to minimal, wich caused the hearts to not appear

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We're tracking this issue in MC-621, so this ticket is being resolved and linked as a duplicate.

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This is not a Duplicate of MC-621. the issue is related only to Axolotl 

I am also having the same issue where the Axolotl are not breeding with tropical fish.