According to specs, that MBA does not support two external displays. Considering that it has only two connection ports that makes sense, as one will typically be used for power input.
MacBook Air (M1, 2020) - Technical Specifications - Apple Support
❝Display Support
Simultaneously supports full native resolution on the built-in display at millions of colors and:
- One external display with up to 6K resolution at 60Hz
Thunderbolt 3 digital video output
- Native DisplayPort output over USB-C
- VGA, HDMI, DVI, and Thunderbolt 2 output supported using adapters (sold separately)❞