The giffgaff goodybags bundles only work in the UK or when roaming in the EU(selected countries). To use the giffgaff services in Turkey you will require airtime credit.
The following charges apply in Turkey:
Data 20p per MB
Calls & voicemail (charged in per second increments after first 30 seconds) £1 per minute
Receiving calls (charged in per minute increments) £1 per minute
Sending texts 30p per text
Receiving texts Free
Picture messages (MMS) to a UK mobile 16p per MMS
Picture messages (MMS) to any other mobile 24p per MMS
You can check out this https://community.giffgaff.com/t5/Using-giffgaff/Using-your-mobile-abroad/ta-p/3522931
link for more details on using the giffgaff services abroad.