Correct Google Sheets Calculation Errors

I'm struggling with my Google Sheets formulas which are not updating and performing incorrect calculations. These issues are also triggering error messages. The data involved is of a financial nature. Freelancers interested in taking on this project should provide information on their experience. They should also ideally possess the following skills and experience:

- Proven proficiency in Google Sheets and its formulas.
- Financial data handling.
- Troubleshooting and rectifying error messages.

Efficiency and attention to detail are paramount for this job.