It is your choice which bet to play with. However, there are exist situations when the game changes your bet.
The bet is automatically changed after:
you close the slot and return to the lobby;
Please note that if you get the Bonus Game that makes you leave the slot (closes the window with the slot and sends you to a new screen), the game resets the bet after you return to the slot.
If that happened to you accidentally, paw-lease feel free to contact us, and we will do our best to assist you!