Hi,
I guess chair will be good and it's not that your body is adjusting with chair but you have to check and do all this below;
chair adjustments: check chair for proper lower back (lumbar)curve, head rest - it should be slightly backwards maintaining proper cervical(neck) curve, arm rest- it should be at proper elbow heights so that there is no shoulder shrugging or shoulder depression, and proper foot support at floor
Laptop or computer adjustment: it should be at proper eye sight level or within 15 to 20 degree angle
Health Tips
advice:
avoid prolong static posture
take shortbreak in between work after every 2 hours atleast
do some simple stretching of neck and upper back muscle( trapezius stretching, pectoral stretching, etc)
if not found relief consult physiotherapist