I took a closer look at the matchmaker and found a mistake. In the transaction in the function findMatchSecondArriver is mutableData empty. That means I don't get into the if condition. The docs of firebase also describes that the currentData of a transaction is always empty at the beginning and you should always do an if(currentData equals null) query.
In my opinion firebase's firestore database is a better solution here. With that one can namely work with the current state of the database. Even at the beginning of the transaction.
If I'm wrong please improve.
I took a closer look at the matchmaker and found a mistake. In the transaction in the function findMatchSecondArriver is mutableData empty. That means I don't get into the if condition. The docs of firebase also describes that the currentData of a transaction is always empty at the beginning and you should always do an if(currentData equals null) query.
In my opinion firebase's firestore database is a better solution here. With that one can namely work with the current state of the database. Even at the beginning of the transaction.
If I'm wrong please improve.