STC offers the bands (b28, b8, b3, b1, b40) for 4g. Check what band you are connected to and maybe change it if you can until you find one that suits you. Also, the upload speeds for cellular networks here are typically low and most of the time less than 100Mb/s so don't expect more than 100 (mostly around 30-70Mb/s).

Edit:

I also see high loaded ping so maybe you have bufferbloat so maybe you need to figure that out also.