Hey @Colleen Stone, thanks for reaching out!
On August 25, we updated AI credit subscriptions and pay-as-you-go (PAYG) billing so they include more AI credits at the same price. This applied automatically and didn't change your subscription cost or PAYG spending limit, it just means more AI credits are available before that limit is hit. You can find the full breakdown in AI credit updates FAQ.
It's also worth knowing how AI credits are drawn down, usage pulls from seat credits first, then any AI credits subscription pool, then pay-as-you-go (if it's enabled) up to whatever spending limit is set. You can find more info here: Manage AI credits.
Was the £30 limit you set a pay-as-you-go spending limit (set from the Billing tab), or a custom AI credit limit for your seat (set from the People tab)? Those work differently, and knowing which one you used will help explain what landed on your invoice.
Since this comes down to the specific charges on your account, I'd like our customer support team to review the actual invoice.
Could you open a request through our Support Hub with a copy of the invoice in question? That'll get it in front of our team who can review this with you directly.
In the meantime, you can check your current AI credits usage and spending limit any time from the AI credits section of your Billing tab.
Thank you,
Gayani