Slow wifi compared to other devices

Dell G5 5500 bought last summer but having trouble with wifi speeds since. Reaching between 0.5 to 6mb/s download speed yet other devices in same room are achieving over 25 mb/s . Upload speed is even worse, currently at 0.08 mb/s. I've searched forums and tried a few suggestions/solutions that fixed the issue for about a month but now I'm having issues again. Would appreciate a more permanent solution as its becoming increasingly frustrating.