Hi. My name is*****'m a camera repair technician with almost 30 years in the business and I'll be glad to help you with your question today.
This usually occurs when either the camera doesn't recognize that there is an AF lens attached or when one of the physical switches on the body or lens is not set to AF. It can also be a fault in the lens. Have you tried other lenses on the camera?
About the only thing you can try is to do a factory reset from the custom functions menu. Anything else will require disassembling the camera to troubleshoot and repair by an experienced camera repairman. You may want to check locally for a camera repair shop in your area, or, if you need assistance finding a shop, please let me know and I'll locate one for you.
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