I've had the same issue, I assumed it was because I was using the new "Mixed Race" teams.
First 2 times it was a Violent Together team in League Cup, after game didn't show the winnings, just went to game synopsis with no SPPs. I assume it's treating the games as Friendlies based on the lack of gold/SPPs.
The 3rd version which has just occurred was in a 2 team Cup where I was farming Amazons to see how the builds in the Far Eastern Mix could combine. This team had played 2 prior matches in a different league which I had quit, and hadreceived gold/SPPs against other teams.
I was using the same 2 team Cup with Violent Together, is it possible it's not saving if the match is the final one?
Another minor bug is when previewing players, it doesn't always display the correct stat line. I preview to change character heads, and was confused to see 5,5,2,9 for a Gutter Runner.
Buying was fine, it's only in the preview screen it's an issue.