My buddy Greg bought a similar pack from a garage sale last spring. He said the chest strap was so tight it felt like a vice after just twenty minutes on the trail. He ended up donating it back and just using an old school bag instead, lol.
Greg's story reminds me of a pack I had where the sternum strap buckle was broken, so it kept sliding down and choking me. I tried to fix it with a carabiner, but that just made it pinch my collarbone. Ended up cutting the strap off entirely and the pack was never quite right after that. Some gear just can't be saved.
Was it the chest strap for you too? I had the same problem with a thrifted pack where no matter how I adjusted it, the straps just cut right into my shoulders. I ended up with sore spots for days after one short hike.