you are likely preparing your return incorrectly. you may be eligible for the foreign earned income exclusion. I strongly suggest you use a tax pro in the country where you reside who is familiar with US taxation. that could be a large accounting or law firm. or you can review form 2555 and the instructions to see if you qualify.
you can use this link International section to see if you qualify)
https://www.irs.gov/help/ita
here is another link that discusses liability for social security and medicare taxes
https://brighttax.com/blog/social-security-us-expat-taxes/#:~:text=As%20a%20rule%20of%20thumb%2C%20e...
form
https://www.irs.gov/pub/irs-pdf/f2555.pdf
instructions
https://www.irs.gov/pub/irs-pdf/i2555.pdf
