My battery condition does not seem normal

Couple of month ago I got the Service Battery warning which warned me to change my battery as soon as possible. I calibrated my battery then. Error was disappeared and everything has been normal since the last calibration. I had got the error again and I did the calibration. subsequently error was gone but by the time my battery has not passed 3 hours concerning the remaining time which is not normal. Usually it used to show at least 6 hours after each fully charged unit. Here is the last condition of my battery's health condition:

Health Information:

Cycle count: 742

Condition: Normal

Battery Installed: Yes

Amperage (mA): -1391

Voltage (mV): 11068

I desperately do not want to change the battery because it is pretty😐 expensive. I would be grateful if you guys help me out.