1. Update your apps. One of you probably doesn't have the latest version (should now be 23.3.0).
2. Don't use the app to plan. It doesn't have enough updates to be reliable. Use a national planner. Normally, that is this one for Poland but currently it does not respond for some reason. The Koleo planner isn't too bad either.
3. For international planning, use the DB planner or DB Navigator app.
4. Reservations within Poland can be done via PKP using this guide, max. 30 days in advance.
5. Reservations for international trains from/to/via Czechia can often be done via CD, max. 60 days in advance.
6. Reservations from/to Germany ar currently only possible at a ticket office that can do international reservations (can be in many countries) or by phone via DB (+49 30 2970, collect at a DB ticket machine). Also max. 60 days in advance.

If you have specific trains you'd like to book, please specify origin, destination, date and departure time, so people can advise.

The trains we need to book reservations are:

Berlin-warszawa zachodnia- 7th August- 17h41-23h12

warszawa Centralna- Krakow Glowny- 9th August- 18h38-20h56

Krakow Glowny-Budapest Nyugati (night train)- 11th August- 23h04-8h20

Budapest Nyugati (night train)-Prague Hlavni Nadrazi (Night train)- 15th August- 19h40-8h42

We were not able to book reservations, what would you advise us? we don´t know anything about this, It´s our first time.. shouldn´t we use the interrail app?

Is the app not reliable? The app just refers to these trains for mandatory seat  reservation. should we rely on this information? the other trains we want to use do not need reservations?

luxembourg-amsterdam

amsterdam-hamburg

hamburg-copenhagen

copenhagen- berlin

prague-vienna

vienna-ljubliana

ljubliana-milano

NO, is NOT reliable-as has been told here dozens of times. Use other-best is bahn.com (can even set to /es/ maybe), as it covers more as this app (but again not all-esp your RENFE  only very partial) AND gets updates 2/week.

Also; to quell your eternal worry (completely unneeded) about REServacion: find the page from seewulf on how to in all countries. Saves you a bundle in extra fees too.

As rian already said; for IN PL on PKP its only FROM 30 days advance-and its not RENFE, so it does not sell out that day so long before.

In fact: except last leg into Milano ALL the CONnexiones (often it means you have to cambio trenes somewhere) are OPTIONal=can do, not need to. For DIRecto HHb->CPH and back must do, but can use other trenes without.

• Berlin-warszawa zachodnia- 7th August- 17h41-23h12: see my first post.
• warszawa Centralna- Krakow Glowny- 9th August- 18h38-20h56: see my first post.
• Krakow Glowny-Budapest Nyugati (night train)- 11th August- 23h04-8h20: should be possible via CD, max. 60 days in advance.
• Budapest Nyugati (night train)-Prague Hlavni Nadrazi (Night train)- 15th August- 19h40-8h42:  CD, max. 60 days in advance.

But the websites is to book the trains and not just seat reservations with the interrail pass, no?

do you think we need to book other trains or just the ones that say is mandatory seat reservation on the app?

Thank you so much for your help

we are from Portugal

You can book reservations there. On the CD website, you can click on "I want a reservation only”; sometimes you first need to add the Interrail discount. For the PKP website, follow their guide.

That entirely depends on the route, date and time of day. If you want advice, please add those (you can edit a post).

luxembourg-amsterdam- 29th July- 13h16

amsterdam-hamburg- 1st August- 18h38

hamburg-copenhagen- 2nd August- 12h53

copenhagen- berlin- 5th August- 00h08

prague-vienna- 17th August- 18h12

vienna-ljubliana- 19th August- 19h05

ljubliana-milano- 23rd August- 05h52

• luxembourg-amsterdam- 29th July- 13h16: no reservation possible.
• amsterdam-hamburg- 1st August- 18h38: you could travel without reservation on a Monday evening but it's only 4€ for the whole journey via DB ("Seat only”).
• hamburg-copenhagen- 2nd August- 12h53: reservation mandatory; 30 DKK via DSB.
• copenhagen- berlin- 5th August- 00h08: you mean the ICE at 00:01? Reservation on Copenhagen - Hamburg is mandatory, book via DSB.
• prague-vienna- 17th August- 18h12: There is no such train. There's a train from Praha Hl.n. at 17:56. Reservation not really needed (train starts in Prague) but is 3€ via ÖBB (“Seat only”).
• vienna-ljubliana- 19th August- 19h05: that is from Wien Meidling. Departure in Wien Hbf (closer to the centre) is 18:58. Reservation not really needed (certainly not in the 2nd train) but possible via ÖBB (“Seat only”).
• ljubliana-milano- 23rd August- 05h52: if you use the Frecciarossa from Venezia Mestre at 12:00, then that is with a mandatory reservation of 10€ via ÖBB (do NOT use "Seat only” but add the "Interrail / Eurail” discount and look for normal tickets).
  If you use regional trains from Venezia Mestre (dep. 11:23), then no reservations necessary:

  

   

Hello again! We have been trying to book the trains from Poland and they don’t ask us for our interrail pass, they just want us to pay the full ticket, what should I do?

also, we booked the Copenhagen trains and they didn’t ask for the interrail ticket, I hope that’s ok

If you used the link above for Danish reservations it is a booking portal for interrail passholders. It should be 60kr per reservation.

For Polish reservations are you using the link for PKP website and guide linked in the second post by rvdborgt? You need to enter train details and on page with train options scroll down to select discounts and enter interrail.

I tried as far as creating account and it seems to work.

I tried but there is only an option for child or youth

do you book trains within poland or cross border to/from poland. 

For trains cross border it is not possible to book online. Only at ticket desks. Like Deutsche Bahn or PKP ICCCC. 

EDIT: Yes Berlin-Warszawa not possible online. 

So, I can only book when I arrive in Germany?

So, I have called every trainline, and the trains to and from poland can´t be booked online! so I can not be sure if there is a place for me on the train! that is really bad

 

For routes it is capable of reserving.

where it says “Number of passengers by normal fare” you should select 0 (this is why it is charging you full fare)

where it says “Number of passengers with discount you should select 1 then it will give a drop down with Interrail option.