diff --git a/Project.toml b/Project.toml
index b72bb8178..d3731e74c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "MixedModels"
 uuid = "ff71e718-51f3-5ec2-a782-8ffcbfa3c316"
 author = ["Phillip Alday <me@phillipalday.com>", "Douglas Bates <dmbates@gmail.com>", "Jose Bayoan Santiago Calderon <jbs3hp@virginia.edu>"]
-version = "4.21.0"
+version = "4.21.1"
 
 [deps]
 Arrow = "69666777-d1a9-59fb-9406-91d4454c9d45"
diff --git a/src/bootstrap.jl b/src/bootstrap.jl
index 786036ae8..fffa62c48 100644
--- a/src/bootstrap.jl
+++ b/src/bootstrap.jl
@@ -180,7 +180,7 @@ families with a dispersion parameter.
 - `hide_progress` can be used to disable the progress bar. Note that the progress
 bar is automatically disabled for non-interactive (i.e. logging) contexts.
 - `optsum_overrides` is used to override values of [OptSummary](@ref) in the models
-fit during the bootstrapping process. For example, `optsum_overrides=(;ftol_rel=1e08)`
+fit during the bootstrapping process. For example, `optsum_overrides=(;ftol_rel=1e-08)`
 reduces the convergence criterion, which can greatly speed up the bootstrap fits.
 Taking advantage of this speed up to increase `n` can often lead to better estimates
 of coverage intervals.