diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 *   Fix cacheing rules for global leaderboard (was previously not saving or
     invalidating cache properly) also for prompt (will not invalidate
     part1-only caches if there is no session key)
+*   **0.2.6.1 Bugfix**: Fix bug in prompt cache invalidation
 
 Version 0.2.5.0
 ---------------
diff --git a/advent-of-code-api.cabal b/advent-of-code-api.cabal
--- a/advent-of-code-api.cabal
+++ b/advent-of-code-api.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 11039e11778c64e34a0031b4251a99a15470033e3dafd1962b1db1a02bcab593
+-- hash: 7c78803c08846a438e524f068966ad9074ebfd7ce45ca61c3e10b611c820e23a
 
 name:           advent-of-code-api
-version:        0.2.6.0
+version:        0.2.6.1
 synopsis:       Advent of Code REST API bindings and servant API
 description:    Haskell bindings for Advent of Code REST API and a servant API.  Please use
                 responsibly! See README.md or "Advent" module for an introduction and
diff --git a/src/Advent.hs b/src/Advent.hs
--- a/src/Advent.hs
+++ b/src/Advent.hs
@@ -443,8 +443,8 @@
   where
     expectedParts :: Set Part
     expectedParts
-      | validToken = S.singleton Part1
-      | otherwise  = S.fromDistinctAscList [Part1 ..]
+      | validToken = S.fromDistinctAscList [Part1 ..]
+      | otherwise  = S.singleton Part1
     sep = ">>>>>>>>>"
     encodeMap mp = T.intercalate "\n" . concat $
                             [ maybeToList $ M.lookup Part1 mp