I live in a condo and the unit above said their kitchen sink is blocked. According to the management office repair guy, he tried using acid but it did not help and need to come to my unit to cut the pipe to clear the blockage. The pipe is located in my unit at the yard area. I think he is not a plumber but just a general repair guy.

Anyone experienced similar issue where they need to cut the pipe to clear the blockage? Is there any other solution besides cutting the pipe as this sound messy and may cause the pipe to leak in the future?