Apparently the plasticity of the brain is lesser in adulthood. Hence; you are going to be more challenged to identify pitch. In fact, musical scholars are claiming that an adult may not be able to develop perfect pitch but with training and could obtain proficiency in “relative pitch”. So, don’t despair, this relative pitch is what we need the most when picking out the next chord in a progression. A key has limitations with respect to which chords are available and consequently the adult brain now gets to work with finite possibilities in relative terms. 

My youtube channel has one song which I posted that I knew didn’t sound right but given the nature of my channel oriented around progress and learning, I didn’t think much of it during the upload. Today, I revisited the song and searched around on “ultimate guitar” (website) to review some reader feedback  associated with the chord structure of the selected piece and discovered two flaws. Somebody with a better ear than mine not only knew it didn’t sound right as scored but he was able to offer the two corrections. I now look forward to the “redo”. The process gives me comfort in that I may be going from the phase of “not knowing what I don’t know” to “knowing what I don’t know” in the context of chord recognition. At this stage of my development, I am still only reaching for a chord because of a memorized sequence and not because of ear sense.  This contrasts to a professional musician who made an exclamation on his youtube channel that he showed up at a weekend festival and was introduced to 18 new songs of which he went right to work on learning and in short order played rhythm for the band in support. The take away is that I must listen more carefully to the sounds instead of anxiously searching my memory.