I am unable to retreat 1 energy retreat pokemon against Feraligatr deck

I was using a Raging Bolt Ex deck fighting against a Feraligatr deck. When s/he bossed my Radiant greninja into the active slot I was unable to retreat the whole fight despite having one energy attached to it. Recently this happened again against a Feraligatr deck but this time my Fezandipiti was in my active slot and i still couldn't retreat despite having energy attached. In the end could only retreat with an item. I'm pretty sure there were no cards used that could affect my retreat at the time. Is this a bug or am I not noticing something?