If you notice a single bet in your history that looks higher than what you normally stake — or even higher than the game's maximum bet — it's almost always because you used the Buy Feature option in the game.
Many slots let you purchase the bonus round or free spins directly instead of waiting for them to trigger. When you do this, the cost of the feature is added to your base bet and shown as one combined amount for that round.
Example: You're betting $2.50 per spin. On one spin you buy the bonus feature, which costs $10. Your bet history will show $12.50 for that spin ($2.50 base + $10 feature).
Your actual stake didn't change — you just bought the bonus once. This is also why the amount can look as out of the betting options than the game's normal bet: the feature cost sits on top and isn't capped by the regular bet limit.
If you're still unsure, contact support and we'll check the specific round for you.
