iFixit battery 120 cycles and "Service Battery" message.

@gct2 ... thank you for your purchase and in supporting the right to repair community.

the battery should be lasting 6-7 hours on normal rated usage (wireless web browsing) anything other than this will deplete the battery faster of course. (the more you use it, the more you charge, the more you charge the life span shortens) your symptom of the decreasing usage time is indicative of a damaged (dry) cell in the battery. no re calibration will help as it is simply one (or more) cells not charging to give power to the device unplugged.

im not sure about the check battery as apple has placed an update to advice about the battery with the last updates if not genuine apple product. (even if it is, if its not serviced and cleared by apple at the time of repair, it will flag)

this being said, if its not working the way it was when you installed it, id replace it again and chalk it up to the way the device is ran and charged. heres a link to the battery for your listed device if needed:

MacBook Pro 13" Unibody (Mid 2009-Mid 2012) Battery

if you feel that something is off and you would like to speak with someone about the technical details and rated longevity of the battery, you can reach out to the service team here:

https://help.ifixit.com/article/50-warra....

the link above has many sections about the warranty descriptions, making a claim and much more.

your purchase comes with a one year warranty, so that has expired…but feel free to reach out there and see what can be done, if anything.