I have a MYSQL and TYPEORM database like Orm, when I start the server, 2 FK columns are added in a table

Question

When I start the server, typeorm logs these changes:

query: ALTER TABLE `topresente`.`classes` DROP COLUMN `class_id`
query: ALTER TABLE `topresente`.`classes` DROP COLUMN `subject_id`
query: ALTER TABLE `topresente`.`classes` ADD `course_id` varchar(255) NOT NULL
query: ALTER TABLE `topresente`.`classes` ADD `class_num` varchar(255) NOT NULL
query: ALTER TABLE `topresente`.`classes` ADD `class_period` varchar(255) NOT NULL
query: ALTER TABLE `topresente`.`classes` ADD `year` varchar(255) NOT NULL
query: ALTER TABLE `topresente`.`classes` ADD `class_id` varchar(255) NULL
query: ALTER TABLE `topresente`.`classes` ADD `subject_id` varchar(255) NULL
query: ALTER TABLE `topresente`.`classes` ADD CONSTRAINT `FK_bd4c6c725acd427f07264770ceb` FOREIGN KEY (`course_id`) REFERENCES `topresente`.`courses`(`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
query: ALTER TABLE `topresente`.`classes` ADD CONSTRAINT `FK_1c29abc497051d41c2d6e276a05` FOREIGN KEY (`class_id`) REFERENCES `topresente`.`classes`(`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
query: ALTER TABLE `topresente`.`classes` ADD CONSTRAINT `FK_a72581b1b6a0ddf0bf5e8bebfc4` FOREIGN KEY (`subject_id`) REFERENCES `topresente`.`subjects`(`id`) ON DELETE NO ACTION ON UPDATE NO ACTION

In the table "classes" 2 columns are added which are "class_id" and "subject_id".

Below is the entity of "classes":

class Class {

    @PrimaryColumn()
    id: string;

    @JoinColumn({ name: "course_id" })
    @ManyToOne(() => Course)
    course: Course;

    @Column()
    course_id: string;

    @Column()
    class_num: string;

    @Column()
    class_period: string;

    @Column()
    year: string;

    @CreateDateColumn()
    created_at: Date;

    constructor(){
        if(!this.id){
            this.id = uuid();
        }
    }
}

I’m not able to reverse this creation, every time I run the application these columns are created.