According to Transfermarkt, is contracted to June 2026, (so 18 months left), he is probably at optimum value now.
It is a "cash in or offer a new contract decision time". These rumours will only strengthen his negotiating position in my opinion.
He turns 26 next month, so also peak age,
I don't see offers in excess of 15m coming in, and therefore on balance would be offering a contract extension if a mutually acceptable package can be agreed.