Present Perfect Usage of "Think" for Recent Past

In a phone conversation like the one below is the present perfect form "I've thought it was Frank on the line" acceptable instead of "thought"?

Matt: Hi John.
John: Hi Frank.
Matt: Oh, this is Matt speaking not Frank.
John: Sorry Matt. I thought it was Frank on the line. You sound very similar.

John's mixing up the voices happens in very recent past (seconds ago) and it has relevance with the present. Why do we generally prefer simple past tense when using the verb "think" in such contexts? In British English present perfect is used commonly for recent past actions and events such as "have told", "has said", "has happened", "have shown" etc. Does it sound natural to use present perfect in such phone conversation context? Can you explain please any linguistic differences?

Solution 1:

In this instance, the difference between "I thought" and "I have thought" is that the former is referring to the immediate present in which there is no past (clearly all previous utterances are temporally in the past but these utterances are immediate rather than past), which applies here, whereas the latter would refer to a past with present relevance.

A situation in which the conversation proceeds without John and Matt knowing about John's mistake until later when John realises that he's talking to Matt and not Frank might elicit from John: "I have thought, until now, that you were Frank but you're Matt, aren't you?".

Solution 2:

For the word "THOUGHT" in a current phone conversation

PAST: I thought it was Frank whom I was talking to yesterday. (no present relevance). I didn't know it was Matt.

PRESENT PERFECT: I have thought, until now, that you were Frank but you're Matt, aren't you?". (there is present relevance)