Can anyone recommend me a Trusted laptop repair technician around Colombo

I have a dell G15 5520 laptop with a power issue i think. So i gave it to the authorized party to repair. Did this by trusting the term "authorized". On the first day they said that they need 4working days to conduct an inspection. Then they will send me the results and then they will perform the repair after my confirmation. But i had to call them after 4 working days to know what is what. Then they told me they started the repair which was a "component level repair" and the issue is in the motherboard. So they didn't inform me about any accurate details about the issue and even started repairing without tell me so. I got a bit freaked out about this behavior and start pressing them by giving calls and asking about the details and status. They never gave accurate info about the issue. When the third time i called i got pissed mainly because all of this was said by the call center people. And i contacted their manager and got the job done next day which was after around 3weeks. I got an email saying that i should pay full by an online transfer. The laptop was fine at first. Then i realized some of the keys arent working as smoothly as it was. Then the issue came back after 5-6hrs.

And i had to take it back and they took another 2weeks or so and told me they couldn't replicate the issue. Then i brought the laptop again and format it because i thought it might fix the issue. Now its as it was before i took it to repairs.

I think they charged me without repairing or changing anything but some software changes. Now the issue is back like it was never fixed. 🫤 Can someone please recommend me a good technician? I need to fix my laptop as well as take actions to this AUTHORIZED REPAIR CENTER.