X and Y had an argument regarding whether Allaah had answered X's supplication correctly according to X's understanding. Y stopped communicating with X because they did not believe what X was telling them. X later contacted Y to inform Y about what had occurred with them. Y was shocked/surprised but did not say anything. X noticed that they were not sending any message as a responce. X decided to tell Y that they forgave them, accepted their apology, that Y does not need to apologize, and that X does not want to know the exact reason(s) why Y mistreated them, because Allaah was concealing their reason(s). However, besides the fact that X believed that Allaah was concealing Y's true reason(s), X did not mean the other statements. X only said those statements in order to encourage Y to say that they were sorry for having committed a mistake, to explain why they had stopped communicating with X, and to somehow make it up with X.
All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
The question is not clear. Lying is to inform of something contrary to what it really is. If this is what happened, then the first person has lied.
Lying is forbidden in principle, and it must be avoided. However, if it is needed as a means to achieve a valid objective that could not be achieved otherwise, then there is no harm in resorting to it. Nonetheless, it is better in all cases to use Tawriyah instead of openly lying. Tawriyah is saying something which has more than one meaning and intending a meaning that is different from what the listener is likely to understand.
Some scholars said that what is meant by lying when reconciling between people is to use Tawriyah, and not explicitly lying.
Allah knows best.
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