Unable to install Signal from App Store on iOS

Each time I try to install Signal Application from App Store on iOS, I get the message:

This item is currently being modified. Please try again later.

How can I install this app on my iPhone?

This issue has been there for about 2 months. There is news that Signal is blocked in my country. I have used a VPN and also I get the same problem.

Either the app developer is pushing out a price/code change, the App Store servers are down, or there's a problem with the app within the App Store.

When developers make a change to the app, including price, it can takes several hours for the change to propagate through the Apple servers. You can keep trying for a few hours and see if this clears itself.

If after 24 hours you still see the same error, you can contact the developer's support (usually from their website) and let them know. It's not uncommon for this happen when the developer hasn't made any changes at all; there's dozens of comments about this throughout the years in the Apple developer forum.

The developer is the one losing revenue so it would be in their best interest to contact Apple about the problem and work with them to resolve it.