Assistance Required Regarding Soldering Issue with DFRobot MEMS CO Gas Sensor Breakout Module

I recently purchased the DFRobot MEMS CO Gas Sensor Breakout Module from your company for use in an air quality monitoring project. While integrating the sensor with my system, I encountered an issue during the soldering of the header pins on the breakout board.

The header pins are not getting properly soldered onto the board, which is resulting in loose connections. Due to this unstable connection, the sensor readings are fluctuating significantly and are not reliable.

I would like to know if you could kindly suggest any alternative method or best practice for establishing a stable connection with the sensor module. If there are recommended headers, connectors, or any specific soldering guidelines for this module, your guidance would be greatly appreciated.

I would be grateful if you could advise on how to resolve this issue or suggest a suitable workaround.