Not happy with the colour pens I bought

In January this year (2020), I bought stationery for myself and my son, with those stationery I also bought colour pens for me for college, I've only used it for 4 weeks now and already when I write the pens stuck, I always believed in this brand because I know it is quality, however these pens are frustrating me as I use it quite often and it cost me almost R30 for these pens.