I was going to say, it's likely clay pipes that collapsed, or tree roots which broke through the pipe. The first time I had that happen it cost me $20 000 to excavate the entire front of the house, plus more to redo the landscape, replace trees, and rebuild my driveway. The repair was guaranteed - but it happened again last March on a tiny part of the sewage line that my neighbour wouldn't let me fix last time because it went across her property. Last year's repair cost me about $5000 all things considered and involved this hole being dug in my driveway. Ironically I just finally started repairs on the driveway today (14 months later) because of Covid restrictions. The driveway is costing me $2000 on top of the $5000 for sewage repair. Plus $2000 for my insurance deductible for repairs inside the house.
Sorry to be a Debbie Downer, but I feel your pain. I hope it's cheaper there.

This is the dig from last March.
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I never give you my number, I only give you my situation.
Beatles