On rare occasions, this might happen. It usually happens because of one of those reasons:
The firmware is out of date: please update your firmware to the latest version on the manufacturer's official website.
Setting issues: please double-check and verify all settings on the miner are correct, including fans, pool, and wallet settings.
Poor ambient conditions: please make sure your miner is not running in hot humid dusty conditions, the poor working environment will have a negative impact on the performance of the miner.
Factory defect: factory defects also cause lower than expected performance. Please contact the manufacturer's official support team to claim the warranty.