Is possible to discard outer brackets in regex and consider inner bracket inside?

I have many patterns with bracket enclosure, I made a regular expression where is not considering brackets and just only what is inside/between them, but exists a problem when the text within brackets contain [] brackets too. Thanks! Regex: (?(?<=\[).*?\[?(?=\])) For example,

A)   [ClusterReceiver            ]
B)   [first-second-third-8050-exec-a       ]

From above, B) is working perfectly, but A) not What is being returned for every case (without quotes): ---

B) "first-second-third-8050-exec-a "
A) "ClusterReceiver[99"

What is desired? ------------------

B) "first-second-third-8050-exec-a "
A) "ClusterReceiver"

The problem is when exist [ ] bracket enclosure within outer [ ] enclosure. The worst case is when exists that problem like A), can you help me by giving a suggestion how to accept at least 1 bracket, in order to have A) as desired "ClusterReceiver" ?