Body Shop Increased Repair Bill By 9k Without Any Approval. What Should I Do?

My car was rear-ended, and repairs are going through at fault drivers insurance State Farm. The shop sends estimate of 15k at the beginning but needed permission to take the car apart. SF then gives permission to take the car apart. Day later the shop submits an estimate of $23.5k. 2 days later the shop then submits a revised estimate (supplement of record something). On this one the estimate goes down to 21k. Approved by SF. They dropped 2.5k. 6 months passed by due to part delays. I visited the shop the other day to see the car as its nearly finished and when asked, found out the estimate was at $30k, but State Farm’s portal still shows $21k as the last estimate. I asked shop if statefarm knows about it, but they said statefarm doesn’t and that adjusters doesn’t like getting estimates every second. But how can they just jump that much without approval and i didnt even past 6 months till now.

State Farm isn’t aware of the $30k, and there might be a $25k policy limit. I haven’t confronted the shop or talked to the adjuster yet, but talked to a rep on Statefarm who confirmed the last estimate of 21k.

What should i do? Will they force me to cover the difference? Should I inform State Farm about the increase ( i know they wont pay over limits but will they work it out with the shop since they proceeded without approval) or bring up the policy limit with the shop?

Also the shop is a statefarm network shop