diff --git a/bot.go b/bot.go
index abef6c0..a9f478a 100644
--- a/bot.go
+++ b/bot.go
@@ -75,6 +75,7 @@ func (b *Bot) BotHandlers() {
 	b.bot.Handle("/say", botSay)
 	b.bot.Handle("/help", botHelp)
 	b.bot.Handle("/transfer", botTransfer)
+	b.bot.Handle("/version", botVersion)
 
 	b.bot.Handle(tb.OnPhoto, botPhoto)
 	b.bot.Handle(tb.OnChannelPost, botChannelPost)
@@ -133,7 +134,7 @@ func botUnpause(m *tb.Message) {
 
 func botDelete(m *tb.Message) {
 	logInfoDebug("[%d] %s(%d) | %s(%d) : delete : %s\n", m.ID, m.Chat.Title, m.Chat.ID, m.Sender.Username, m.Sender.ID, m.Text)
-	r := regexp.MustCompile("/delete (?P<CompanyID>[0-9]+)")
+	r := regexp.MustCompile("\\/delete (?P<CompanyID>[0-9]+)")
 	id := uint8(255)
 	if r.MatchString(m.Text) {
 		ID64, _ := strconv.ParseInt(r.ReplaceAllString(m.Text, "${CompanyID}"), 10, 64)
@@ -238,7 +239,7 @@ func botGive(m *tb.Message) {
 		return
 	}
 
-	r := regexp.MustCompile("^/give @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
+	r := regexp.MustCompile("^\\/give @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
 
 	if !r.MatchString(m.Text) {
 		bot.SendChat(m.Chat.ID, "Wrong format.")
@@ -270,8 +271,18 @@ func botGive(m *tb.Message) {
 	bot.SendChat(m.Chat.ID, fmt.Sprintf("@%s now has %s left.", uStr, cc.TimeLeft.Round(time.Second)))
 }
 
+func botVersion(m *tb.Message) {
+	bot.SendChat(m.Chat.ID, version)
+	return
+}
+
 func botTransfer(m *tb.Message) {
-	r := regexp.MustCompile("^/transfer @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
+	r := regexp.MustCompile("^\\/transfer @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
+
+	if !r.MatchString(m.Text) {
+		bot.SendChat(m.Chat.ID, "Wrong usage.")
+		return
+	}
 
 	ccFrom, ok := cfg.Clients[m.Sender.ID]
 	if !ok {
@@ -318,7 +329,7 @@ func botTake(m *tb.Message) {
 		return
 	}
 
-	r := regexp.MustCompile("^/take @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
+	r := regexp.MustCompile("^\\/take @(?P<Username>[a-zA-Z0-9]+) (?P<Duration>[a-z0-9]+)")
 
 	if !r.MatchString(m.Text) {
 		bot.SendChat(m.Chat.ID, "Wrong format.")
@@ -363,9 +374,10 @@ func botHelp(m *tb.Message) {
 	msg = fmt.Sprintf("%s/players    - list players\r\n", msg)
 	msg = fmt.Sprintf("%s/give       - give time to player\r\n", msg)
 	msg = fmt.Sprintf("%s/take       - take time from player\r\n", msg)
-	msg = fmt.Sprintf("%s/transfer   - transfer time to player\r\n", msg)
+	msg = fmt.Sprintf("%s/transfer   - transfer time between players\r\n", msg)
 	msg = fmt.Sprintf("%s/passwd     - change passwd\r\n", msg)
 	msg = fmt.Sprintf("%s/say        - send msg to the game\r\n", msg)
+	msg = fmt.Sprintf("%s/version    - version\r\n", msg)
 	msg = fmt.Sprintf("%s/help       - this\r\n", msg)
 
 	bot.SendChat(m.Chat.ID, msg)
@@ -426,6 +438,46 @@ func botPasswd(m *tb.Message) {
 }
 
 func botDeregister(m *tb.Message) {
+	r := regexp.MustCompile("^\\/deregister @(?P<Username>[a-zA-Z0-9]+)$")
+	if r.MatchString(m.Text) {
+		if m.Sender.ID != int(cfg.Telegram.AdminID) {
+			bot.SendChat(m.Chat.ID, "Not admin.")
+			return
+		}
+
+		uStr := r.ReplaceAllString(m.Text, "${Username}")
+		var uID int
+
+		for ccID, cc := range cfg.Clients {
+			if cc.Username == uStr {
+				uID = ccID
+			}
+		}
+
+		if uID == 0 {
+			bot.SendChat(m.Chat.ID, "No such user found.")
+			return
+		}
+
+		cc := cfg.Clients[uID]
+
+		if cc.CompanyID != 255 {
+			for coID, co := range srv.Status.Companies {
+				if coID == cc.CompanyID {
+					cc.CompanyID = 255
+					bot.SendChat(m.Chat.ID, fmt.Sprintf("Deregistered from %s. %s playable left.", co.Name, cc.TimeLeft.Round(time.Second)))
+					return
+				}
+			}
+			logInfoAlert("botRegister : %s : no such CompanyID : %d", cc.Username, cc.CompanyID)
+			cc.CompanyID = 255
+			bot.SendChat(m.Chat.ID, fmt.Sprintf("Registered company didn't exist anymore. %s playable left.", cc.TimeLeft.Round(time.Second)))
+			return
+		}
+
+		return
+	}
+
 	cc, ok := cfg.Clients[m.Sender.ID]
 	if !ok {
 		cc = &ClientConfig{
@@ -566,7 +618,7 @@ func botQuery(q *tb.Query) {
 }
 
 func botText(m *tb.Message) {
-	r := regexp.MustCompile("^/delete_(?P<Ref>[a-f0-9]{16})$")
+	r := regexp.MustCompile("^\\/delete_(?P<Ref>[a-f0-9]{16})$")
 	if r.MatchString(m.Text) {
 		ref := r.ReplaceAllString(m.Text, "${Ref}")
 		d, ok := companyDeleteMap[ref]
diff --git a/config.go b/config.go
index 6d6b103..98f5ba5 100644
--- a/config.go
+++ b/config.go
@@ -101,6 +101,9 @@ func (c *Config) Export() ([]byte, error) {
 }
 
 func (c *Config) CompanyIsRegistered(id uint8) bool {
+	if id == 255 {
+		return false
+	}
 	for _, cc := range c.Clients {
 		if cc.CompanyID == id {
 			return true
diff --git a/version.go b/version.go
index 3796a07..f283e6c 100644
--- a/version.go
+++ b/version.go
@@ -1,6 +1,6 @@
 // Code generated by version.sh (@generated) DO NOT EDIT.
 package main
-var githash = "cd98db8"
-var buildstamp = "2021-11-28_13:25:25"
-var commits = "209"
-var version = "cd98db8-b209 - 2021-11-28_13:25:25"
+var githash = "3b878e0"
+var buildstamp = "2021-11-28_13:40:44"
+var commits = "210"
+var version = "3b878e0-b210 - 2021-11-28_13:40:44"