Found this on the web but do not have any feedback on the repair services.
https://www.joesge.com/pages/rlfs-issue-repair?p=surge&cache=false
Best AnswerI've never heard of them but they have a friendly 'about' story and claim you can call directly and reach a live human, so there's that. Their price (stated as an estimate) for battery replacement is ~$50USD, and batteries are ~$12 on eBay or AliExpress. If you're not comfortable repairing your device, and indeed, this guy has experience working with multiple devices, it might be a good affordable solution to keep your old tracker. I can't speak to their quality, though did notice the website's been up ~5 years, and that's a good sign. Let us know if you try it 😉