First time O2 sensor issues

Hi all. I have a 2008 3 hatchback that recently flashed some codes:
P0131- HO2S-11 (Bank 1 Sensor 1) Circuit Malfunction
P0138 HO2S-12 (Bank 1 Sensor 2) Circuit High Input
P2251 A/F Sensor Negative Current Control Circuit Open

I'm at 93K miles, so I feel like I can safely assume both sensors are probably beat? But one of them is somewhat expensive, so if it could possibly be something that wouldn't necessarily require replacing both, that'd be cool. I know very little about cars, for the record...any thoughts?

Thank you!