Character won't rejoin party, says I have too many troops

[Dujek1arm]

After disbanding a supply wagon, the character sent to lead it cannot rejoin the group as it says "No I have too many troops to keep track of" despite there being room for more troops in the party. The character repeatedly asks the question, preventing my character from continuing on.
Mod 8.6

[Dujek1arm]

Another pic

[Dujek1arm]

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