Buy player from transferlist

[Bassie1991_NL]

At the transferlist there's a player from an other team in our league.
The other manager is asking a lower price for the player than it's value. I want to buy his player for the price he's asking. But I can't, I have to do an offer instead of direct buying. Is this a bug??

How can I directly buy his player from the tranferlist?

[Bassie1991_NL]

for the record, I'm playing with the IOS app.