The Argentine announced on Friday that he would be staying at the Camp Nou for another season, just a few weeks after sending a secure message to the club informing them of his desire to leave.
Messi and his advisers felt that a clause previously placed in his contract allowing him to leave on a free remained valid, but Barcelona refuted the claim and refused to let him leave for any less than his 700m release clause.
The 33-year-old did not want to press the club into legal action and so his only option was to remain for another year, with his contract due to expire in the summer of 2021.
And Sanchez feels the entire situation arose because Messi is not being given the best advice from those around him.
He told ESPN: "That untimely burofax only strengthened the image of the president of Barcelona and gave him time to weaken Messi's decision.
"Messi has had no choice but to stay at Barcelona due to bad advice from his father and the law firm, because they could have saved that burofax. That has caused weakness to his image within the team.
"If Messi and his father already had the decision to leave Barcelona, they should not have waited. Before the end of the term agreed in the contract, they had to tell the club that they wanted to leave at the end of the season and on a free, without paying any compensation.
"If they had it planned, it should have been done that way."