Sounds like a nocking point /brace height issue. Probably nocking point is set too low.
When I measure nocking point placement, I do it with the bow strung. Then I use a tape measure and pull from the top limb tip to the nock. The brace height needs to be set correctly before taking the measurement.
I’d put your old string on the bow, shoot it and make sure the brace height is right. Then measure both brace height and nocking point placement. Then duplicate what you recorded for the old string on the new string.