My first guess is Trump is actually somewhat pissed at Putin for not making a deal, because it makes Trump look powerless. Unlike everyone who knew anything about the conflict, he probably believed Putin would be happy to do a quick, transactional deal if Ukraine was pressured to make big concessions. Putin going "nah I'm winning*, give me everything or no deal" makes Trump not the main character
* IMO he's not, but he claims and possibly believes he is