You can only use 2 days of any interrail pass in your home country, these are marked as outbound and inbound days.

Any further attempts to use a pass in your home country after you have used up these will not be allowed in the app and all other days the pass is clearly marked as invalid for your country.

Thank you for your reply.

I would like to make the following journeys. Could you please let me know if this is still feasible with the pass I purchased (4 day interrail Global pass)

6th May: Hamburg to Frankfurt, Frankfurt to Hamburg

25th May: Hamburg to Prague

28th May: Prague to Hamburg

4th June: Hamburg to Frankfurt

Also, please guide me which of them will be inbound/outbound journeys? Do I need to select or deselect them as inbound/outbound journeys or should I leave it to app to decide?

Thank you and best regards,

Hrishikesh

No. You can only use a global Interrail pass for 2 days for travel in Germany. Your plan is 4 days with travel in Germany, this is not allowed on an interrail pass.

Had you bought a Eurail pass as suggested in your other thread this would be possible as there is no such restriction.

As you bought the Interrail pass and not a Eurail pass you can only travel on a maximum of 2 travel days in your country of residence (Germany). You will need to buy normal tickets for 2 of your travels in Germany.

You are right, I was confused whether I qualify for eurail or interrail pass reading explanation on eligibility of the passes. Any idea if it is possible to cancel the pass (I havent made any journey yet). How much amount is typically refunded?

If you can make an exchange of passes then the fee is 15 EUR. A refund would cost 15% of the pass price. 

https://www.interrail.eu/en/interrail-passes/ordering-info/refund-exchange-policy

To make an exchange, first deactivate the pass, if it has been activated already.

Thanks a lot for your kind help, everyone! This is a great community center!