golang mariadb ping failed "driver: bad connection"

mariadb version: 10.5.22

db.Ping() returns driver: bad connection

package main

import (
    "database/sql"
    "log"
    "net/http"
    "os"
    "time"

    "github.com/gin-gonic/gin"

    _ "github.com/go-sql-driver/mysql"
)

func main() {
    db, err := sql.Open("mysql", os.Getenv("DATABASE_URL"))

    if err != nil {
        log.Fatal(err)
    }

    db.SetMaxOpenConns(25)
    db.SetMaxIdleConns(25)
    db.SetConnMaxLifetime(2 * time.Minute)

    router := gin.Default()

    api := router.Group("/api")
    api.GET("/health", func(c *gin.Context) {
        err := db.Ping()

        if err != nil {
            c.JSON(http.StatusInternalServerError, gin.H{
                "error": err.Error(),
            })
            return
        }

        c.JSON(http.StatusOK, gin.H{
            "message": "OK",
        })
    })

    if err := router.Run(":8080"); err != nil {
        log.Fatal(err)
    }
}

server logs:

[mysql] 2024/07/09 02:04:23 connection.go:49: unexpected EOF
[mysql] 2024/07/09 02:04:34 connection.go:49: unexpected EOF
[mysql] 2024/07/09 02:04:44 connection.go:49: unexpected EOF

I have tried playing with various db settings but no luck.

    db.SetMaxOpenConns(25)
    db.SetMaxIdleConns(25)
    db.SetConnMaxLifetime(2 * time.Minute)

My password was not being parsed correctly because it has special character. Using formatDSN() fixed my problem.