Within your country, depending on where you are located, service and support
may vary from the ideal. There may be other Authorized service providers who
could do a better job with a correct diagnostic and suitable repair.
Find an Apple Authorized Service Provider:
https://locate.apple.com/country
Where you are located and the absence of official Apple Store and/or
(more than one) Authorized Apple Service Provider, is a big problem.
A neighboring country may have an option, if you could trust it and
not pay customs; and freely travel or have item shipped cost effective.
If your Country isn't listed in their Locator site, there may be a listing in the
more general Region. In some instances, when a country is not listed there
may be a second area. Then some regions only have independent business
who may repair and/or sell who do not have official status with Apple, Inc.
Not sure who you could contact and don't know where you are located.
Is the product newer & still covered under an extended AppleCare plan?
Here's a general Apple.com Contact page: https://www.apple.com/contact/
Because these Apple Support Communities have no 'staff' and most of those
who reply to questions do so on our own time, without compensation, also; we
do not represent Apple and are not employees of the company. Anyone can
try & help others by reading enough to attempt to help resolve issues, or by
having learned and used their products on our own time & our own dime.
Sorry that you haven't gotten headway through your local or regional authorized
Apple independent reseller who may also be the authorized repair agency there.
If you are having to pay for each repair attempt, there may be a local governing
consumer protection law and office to report bad business practices there.
Hopefully you can talk to someone else, or find if someone repairs Apple items
outside your area and if they accept shipped products for service from your area.
What isn't working correct in your Mac? Which model and OS X has it?
In any event:
Good luck in this matter...! 😐