Narrative:

After crossing janny intersection; on the arrival to oxr; joshua approach handed us off to socal approach. I was the pilot monitoring and switched to appropriate frequency. After check-in; socal issued us a descent to 4;000 feet. I read back the new altitude assignment and pilot monitoring set the new altitude and initiated the descent. At approximately 4;500 feet socal issued a low altitude alert and said to maintain 5;000 feet. I stated to the controller that he issued us 4;000 feet and we read that back to him with no corrections from him. There was no further mention of the event from the controller. Pilot flying initiated a climb back to 5;000 feet. At approximately 4;900 feet we were issued a traffic alert and told to descend to 4;000 feet.

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Original NASA ASRS Text

Title: General aviation flight crew reported receiving low altitude alert from ATC with altitude reassignment.

Narrative: After crossing JANNY intersection; on the arrival to OXR; Joshua Approach handed us off to SoCal Approach. I was the Pilot Monitoring and switched to appropriate frequency. After check-in; SoCal issued us a descent to 4;000 feet. I read back the new altitude assignment and Pilot Monitoring set the new altitude and initiated the descent. At approximately 4;500 feet SoCal issued a low altitude alert and said to maintain 5;000 feet. I stated to the controller that he issued us 4;000 feet and we read that back to him with no corrections from him. There was no further mention of the event from the controller. Pilot Flying initiated a climb back to 5;000 feet. At approximately 4;900 feet we were issued a traffic alert and told to descend to 4;000 feet.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.