diff --git a/FAQ.md b/FAQ.md
index 18f7e63..4a9cce5 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -931,7 +931,7 @@ After making the payment, please refresh the license [as below](https://github.c
 
 # Is it over charge in upgrade?
 
-> User: We needed to add 100 additional client licenses and were charged $500, pay all at once.  It should have been $.1 * 100 * 12 = $120.  We need to be refunded the difference.
+> User: We needed to add 100 additional client licenses and were charged $500, pay all at once. It should have been 0.1 * 100 * 12 = $120.  We need to be refunded the difference.
 > 
 > RustDesk: The license expiry date is extended to a full year, as explained [here](https://github.com/rustdesk/rustdesk/wiki/FAQ#renew--upgrade-license). The current date is August 14, 2025. Your existing license covers 10 users and 800 devices, with an expiry date of March 12, 2026. You are upgrading the license by adding 100 devices, and the license is extended for a full year, so the new expiry date is August 14, 2026. The charge is divided into two parts:
 > - Part 1: The cost for the new 100 devices for 12 months is calculated as: 0.1×100×12=120 USD