gin-gonic templates only ever showing one form - go

Question

I have been setting up my gin templates to use a base template that sets out the layout for my various views.
The problem I am having is that all views show my Register page, no matter what route I navigate to. All my templates inherit from base and define content when they are called and are all loaded initially when my application starts with LoadHTMLGlob().
What I expect to see is when each page is visited, the content block is inserted into the layout defined in my base template, but on every request I just see the register view.
Looking at the logs, I am getting 200 messages so the routing appears fine, also when I insert some dummy text into the content block of base it renders fine.
What am I missing below or in general to get this working properly?
Login handler for the /login route
func getLoginForm(c *gin.Context) {
c.HTML(http.StatusOK, "login.html", nil)
}
Loading templates in main()
router.LoadHTMLGlob("templates/*")
router.Static("/public", "./public")
base.html
{{ define "base" }}
{{ template "header" .}}
{{ template "navbar" .}}
{{ template "flash_messages" .}}
{{ block "content" .}}
{{ end }}
{{ template "footer" .}}
{{ end }}
index.html
{{ template "base" }}
{{ define "content" }}
{{ template "site_image" .}}
{{ end }}
register.html
{{ template "base" }}
{{ define "content" }}
<form method='POST'>
<br>
<div class="mb-3">
<label for="email">Email address</label>
<input name="email" type="email" class="form-control" id="email" placeholder="Enter email">
</div>
<div class="mb-3">
<label for="username">Username</label>
<input name="username" type="username" class="form-control" id="username" placeholder="Enter username">
</div>
<div class="mb-3">
<label for="password">Password</label>
<input name="password" type="password" class="form-control" id="password" placeholder="Enter password">
</div>
<div class="mb-3">
<label for="confirmPassword">Confirm Password</label>
<input name="confirmPassword" type="password" class="form-control" id="confirmPassword" placeholder="Confirm password">
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
{{ end }}
login.html
{{ template "base" }}
{{ define "content" }}
<form method='POST'>
<br>
<div class="mb-3">
<label for="username">Username</label>
<input name="username" type="username" class="form-control" id="username" placeholder="Username">
</div>
<div class="mb-3">
<label for="password">Password</label>
<input name="password" type="password" class="form-control" id="password" placeholder="Password">
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
{{ end }}