When reading most, if not all, books on Jinn and Ruqya, it is usually stated that one shouldn't seek help in using Jinn against Jinn or other things. At least that is what i saw in the books i have seen on the subject.

Recently a group of friends who, themselves and their families, are having problems with Jinn and Magic have started communicating with Jinn in order to combat the problem. This may entail communicating with jinn who are possessing people and making Dacwa to them or threatening them or convincing them to leave.
Magical Talismans To Succeed In Life, Protect Yourself From Others And Summon Spirits. (Instructions and techniques on how to communicate with spirits)
Learn more
Maximillien de Lafayette When dealing with a 'good' jinn, that jinn may give news about all the other jinn, may be able to locate and throw out the magic (while saying it is only possible by Allah), call other Jinn to come in order to communicate with the people, and things similar to it.

The situation has advanced so that the brothers may ask the jinn to inform them about who sent the magic and why. They also ask the jinn about people who may have gone missing years and years ago.

They say there is a fatwa which states that using jinn is allowed in what is good. They also say there are various words from some scholars.

Any information on this issue? If allowed, what are the limits? How can one trust a jinn?

Please respond those who have knowledge on this or who can do quick research. any good sources on this topic would be appreciated.

jzk