I'm not an AGP installer, so this is not a question I can answer on my own. I poked around in past threads here, and on a number of other forums. It turns out the question, "Why are my AGP's walls buckling?" has been asked a LOT more times than it has been answered. As best I can tell, the two most likely answer are (1) an over-tensioned liner or (2) a pool base that is not completely level and stable. Please note that the liner may be OK on a hot day, but shrink enough when cold water is added, to cause a problem. The picture below, from the Artesian pool manual, illustrates the problem:



You may want to check out these install manuals, as well:

http://www.doughboy-pools.com/Servic...G01DBSigOv.pdf
http://www.propools.com/instructions...structions.pdf
https://www.poolsupplies.com/pdfs/artesian-round.pdf