Taking a look into the code :
The spellcheck.alternativeTermCount Parameter
Specify the number of suggestions to return for each query term existing in
the index and/or dictionary. Presumably, users will want fewer suggestions
for words with docFrequency>0. Also setting this value turns "on"
context-sensitive spell suggestions.
This parameter , if set to 0, should basically avoid suggestions if you get
a correctly spelled term.
The default value is 0 for that.
So it is weird you get the suggestions, you could debug that bit and see,
unfortunately I don't have time right now !
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