If it helps, I have found that the non aspire davide, (the ones that use the kanger heads), do sometimes air lock in the base when filling. Quick remedy, with the tank right way up, tilt slightly and tap on the side, to get any trapped air to come up through one of the fill holes.
Don't know if this would be the same for the aspire ones, as I've not got one yet.
There are two types, the anyvape davide, and the aspire davide. Plus there is a protank aspire adaptor, that might fit. Not bought one yet, so don't know. But someone else might.