Sounds like door handle carrier failure.
Search around, there are plenty of those here. It is not difficult to replace. People have mixed results with non-oem carriers. One of those is me. My admittedly cheap carrier only works every once in a while, but its not in full failure mode like my old one that actually broke. Eventually, you cannot open the door from the outside at all.

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2001 E53 3.0 5pd