When do trades between two countries not result in gains for either of them? So are there any circumstances where two countries trade with each other and they both do not gain anything? is it possible? and if you could also explain why that is the case? I have looked around and haven't really been able to find any answers.

Thanks in advance
The reason you probably find it hard to think of a case where this happens is because rarely do countries go around trying to make poor trades (read: never). If you trade real goods, there will almost always be a comparative advantage of trade to be had as long as countries have different production possibility frontiers in different ratios. Different opportunity costs of making more of one good means you might want another countries' labor to offer that service.

I can't give any specific examples of trades that were bad for each party where each party also was trying to act in there own self interest. Maybe if two countries were trading public debt with each other before a recession, they might end up with riskier assets than they bargained for, so even though the expected value of the debt was worth enough before a negative growth shock, you might get something less favorable in practice. Even then I don't think a situation like that is very likely to happen.