I Am Taking Bupropion HCL XL, A Substitute For Wellbutrin.

I am taking Bupropion HCL XL, a substitute for Wellbutrin. The tablets I got from the pharmacy do not match those I have been taking over the last few months. They are oval, not round, and are marked with I L and then the roman numeral for 1. I cannot find a match on any of the online forums. Have I been given the wrong drug? Thanks.