Varnish Cache VCL error ('Expected CSTR got 'sub') - varnish-vcl

Question

Somehow there is a big problem regarding the varnish cache and how it works.
I have 2 servers that run the same Varnish configuration, and some vcl files and the main one gets this error on only one of the servers:
May 28 17:20:06 VCL compilation failed
May 28 17:02:55 server1 systemd[1]: varnish.service: control process exited, code=exited status=255
May 28 17:02:55 server1 systemd[1]: Failed to start Varnish Cache, a high-performance HTTP accelerator.
May 28 17:02:55 server1 systemd[1]: Unit varnish.service entered failed state.
May 28 17:02:55 server1 systemd[1]: varnish.service failed.
May 28 17:20:06 server1 systemd[1]: Starting Varnish Cache, a high-performance HTTP accelerator...
May 28 17:20:06 server1 varnishd[27860]: Could not delete 'vcl_boot.1653742206.480069/vgc.sym': No such file or directory
May 28 17:20:06 server1 varnishd[27860]: Error:
May 28 17:20:06 server1 varnishd[27860]: Message from VCC-compiler:
May 28 17:20:06 server1 varnishd[27860]: Expected CSTR got 'sub'
May 28 17:20:06 server1 varnishd[27860]: (program line 378), at
May 28 17:20:06 server1 varnishd[27860]: ('/etc/varnish/default.vcl' Line 27 Pos 1)
May 28 17:20:06 server1 varnishd[27860]: sub vcl_recv {
May 28 17:20:06 server1 varnishd[27860]: ###-----------
May 28 17:20:06 server1 varnishd[27860]: Running VCC-compiler failed, exited with 2
May 28 17:20:06 server1 varnishd[27860]: VCL compilation failed
May 28 17:20:06 server1 systemd[1]: varnish.service: control process exited, code=exited status=255
May 28 17:20:06 server1 systemd[1]: Failed to start Varnish Cache, a high-performance HTTP accelerator.
May 28 17:20:06 server1 systemd[1]: Unit varnish.service entered failed state.
May 28 17:20:06 server1 systemd[1]: varnish.service failed.
And the other one just works perfectly.
the errors above are just examples, the first one was regarding the xforward.vcl that is shorter to put here and it looks like this:
sub vcl_recv {
if (req.http.X-Forwarded-For) {
set req.http.X-Forwarded-For =
req.http.X-Forwarded-For + ", " + client.ip;
} else {
set req.http.X-Forwarded-For = client.ip;
}
}
And here is the head content of my default.vcl:
sub vcl_recv {
# First we must fix the redirect loop that we might hit while using WordPress:
# For this you have to find a header in wp-config.php file of that domain
# for the configuration in the wp-config.php file I will put it in the
# README.md file
# [loop_error_fix]
set req.http.X-Forwarded-Proto = "https";
# [LetsEncrypt Certbot Passthrough {default2.vcl} ]
if (req.url ~ "^/\.well-known/acme-challenge/") {
return (pass);
}
.....
but just like the error above it gives Expected CSTR got 'sub'.
I was wondering is there something wrong with varnish!?
Varnish version:
varnishd -V
varnishd (varnish-6.6.2 revision 17c51b08e037fc8533fb3687a042a867235fc72f)
Copyright (c) 2006 Verdens Gang AS
Copyright (c) 2006-2020 Varnish Software
In any case here is the ERROR on the xforward.vcl:
May 28 17:20:06 server1 varnishd[27860]: VCL compilation failed
May 28 17:20:06 server1 systemd[1]: varnish.service: control process exited, code=exited status=255
May 28 17:20:06 server1 systemd[1]: Failed to start Varnish Cache, a high-performance HTTP accelerator.
May 28 17:20:06 server1 systemd[1]: Unit varnish.service entered failed state.
May 28 17:20:06 server1 systemd[1]: varnish.service failed.
May 28 17:42:26 server1 systemd[1]: Starting Varnish Cache, a high-performance HTTP accelerator...
May 28 17:42:26 server1 varnishd[5089]: Could not delete 'vcl_boot.1653743546.450277/vgc.sym': No such file or directory
May 28 17:42:26 server1 varnishd[5089]: Error:
May 28 17:42:26 server1 varnishd[5089]: Message from VCC-compiler:
May 28 17:42:26 server1 varnishd[5089]: Expected CSTR got 'sub'
May 28 17:42:26 server1 varnishd[5089]: (program line 378), at
May 28 17:42:26 server1 varnishd[5089]: ('/etc/varnish/lib/xforward.vcl' Line 9 Pos 1)
May 28 17:42:26 server1 varnishd[5089]: sub vcl_recv {
May 28 17:42:26 server1 varnishd[5089]: ###-----------
May 28 17:42:26 server1 varnishd[5089]: Running VCC-compiler failed, exited with 2
May 28 17:42:26 server1 varnishd[5089]: VCL compilation failed
May 28 17:42:26 server1 systemd[1]: varnish.service: control process exited, code=exited status=255
May 28 17:42:26 server1 systemd[1]: Failed to start Varnish Cache, a high-performance HTTP accelerator.
May 28 17:42:26 server1 systemd[1]: Unit varnish.service entered failed state.
May 28 17:42:26 server1 systemd[1]: varnish.service failed.
If there is something that I'm missing I'll be glad if you could help me out.
Thanks