Ipad or Android tablet? If it’s Android look up how to reset using recovery mode (model of tablet). Generally it’s hold the home button, power button and volume down/up depending on model to turn it on and you can factory reset from there. Might not work depending on how it was set up as a “work” tablet but worth a try. If that doesn’t work and it’s still managed by your work when you reset it then you’d have to use a custom rom.
As long as everything is working, do a battery replacement and make sure you regularly backup everything. Expect it to die sooner than it would have, but ride it till it dies.