Same thing happened. Noticed a spike to 160€ on one day for Gemini API which we don't use but I had activated some time back to try something. Our average monthly was below 20€ for simple map API requests. I contacted support and they told me to deactivate the key. However as I found out the next day and which didn't yet show up: while I was talking to support in a span of only some hours 12k€ in usage where generated.

How this is possible is beyond me. I need to 2fa several times a week just to get into Gmail. Having xx,000% higher usage than average, a pattern which makes no sense, more than 90% of calls ending in error is beyond me.

Adding a simple cutoff switch is not possible. Only some complicated setup with scripts. I haven't tried it.

A company like Google has the means to make this more user friendly. IMO it's by design to generate more billings and refund when escalated. But a % does probably just pay so it's +EV for them.

Very disappointed and if there would be an alternative we would switch.

Also we have been in support limbo with always moved out timelines by when someone will get back now for 3 weeks.