not able to send a message for the resolution of a case: "You don't have permission to access ..."

[masc.pierr]

This is the message that the page gives me when I try to send a message to a seller, about an item that hasn't arrived yet:

"
You don't have permission to access "http://www.ebay.es/res/ItemNotReceived/SendMessage?" on this server.

Reference #18.2c0e08c3.1611236277.250cf286

"

Please help. I need to contact the seller to resolve this case.

[eburtonlab]

I see you are registered in Portugal, and you are trying to respond to a case on eBay Spain.

"Access Denied" errors when trying to check out or pay or use eBay messages usually indicate some sort of network error.

If you are using a VPN, try disabling it.

If you are using a custom firewall, that may be causing problems.

Try responding to that case using your phone or laptop when not connected to your usual network wifi.

See here for further suggestions of things to try:

https://community.ebay.com/t5/Technical-Issues/Access-Denied/m-p/29845776#M56948