Despite an agreement with Manchester City, the player is planning to sign a new contract

Although the news that Manchester City and Valentin Barco had reached a verbal agreement first seemed fantastic, we now see various barriers standing in the way of this transfer.

Man City swoop in to sign Brighton's next South American gem! Valentin Barco  set to join treble winners for £8m from Boca Juniors despite Seagulls  interest | Goal.com India

The Argentine media has been reporting that Boca Juniors will attempt to retain the player by extending him a new contract ever since the rumor about a verbal agreement surfaced.

The Manchester City target is reportedly planning to extend his contract with the Buenos Aires side, according to TNT Sports.

El City fichará a Valentín Barco, la nueva perla de Boca

According to their source, Barco is anticipated to sign a new deal immediately following the Copa Libertadores semifinal matches against Palmeiras, which are scheduled for September 29 and October 5.
The fullback will now be committed to Boca Juniors till 2028 on this new contract. What’s more, his release clause would increase from US$10 million to US$20 million.

Alerta en Boca Juniors: el club sensación de la Premier League negocia para  comprar a Valentín Barco - Infobae

Manchester City had better brace ready for further difficult negotiations with the Argentine club if they truly expected to spend so little on his signing. If the report is accurate and the contract is signed, then.