Typically, when a fuse blows immediately upon connection, it suggests that there may be a short circuit within the radio's power input circuitry. Often, this is due to a shorted protection diode, which is designed to prevent damage to the radio from voltage spikes or reverse polarity connections. If the diode is compromised, it can create a direct path to ground, causing the fuse to blow to protect the rest of the radio's components.
Please, do not attempt to bypass the fuse or use a higher rated fuse, as this could cause further damage to your radio or create a safety hazard. Instead, I would recommend having the radio inspected by a qualified technician who can diagnose and repair the issue safely and effectively.