I have been having issues and believe its the lights

due to laws of conservation of mass and energy (light has both aspects), distance does not gain or reduce umol/s that your light produces. it does get more spread out. That's the inverse square law. if working at 30cm, 1/2 that distance would be 4x more intense light, but in a smaller area of coverage. whether this is an autoflower or a photoperiod will matter too. Hours of light per day is part of the equation. 18 hours is 50% longer, needs 33% less light. 12 hours is 33% fewer and need 50% more light over that 12 hours. if you do 20 or 24, you cna do the math. i'm going to work with "12 hours" you want a minimum of 500 PPFD. That's 500 umol/s per m^2. Again, this is proporitonal. 1/2 m^2 only need 250 umol/s as minimum. So, this is relative to area as well as time. without added CO2, or simply ambient atmospheric CO2, ~800-900 PPFD is your ceiling for 12 hours. A DLI chart can help here. ~40DLI is about as high as you want to go. Technically 43.something, but that requires lab precision in all other relevant factors. a dli chart will verify all the things i just said for the "12 hour" row. You can work backward from the same PPFD values relative to how many hours per day you run your lights (apples to vegetative phase too). What cuases concern is their specifications... this is a giant red flag of incompetence and a lack of understanding. If it is 564 umol/s, i wouldn't use it to flower(12 hours) any area larger than 1m^2. How high? let plants tell you. They wilt and otherwise try to avoid light if it is too much... if you continue to stress them in that way, they will form pale spots that quickly encompass entire leaves near top. This damage cannot be healed if it goes too far. You'd know it when you see it, just preparing you. So, let plant dictate height.. maywant to take note of height per phase too... Seedlings quicly want intense light, but they can handle a bit more as the mature. I'd set height based on coverage, if PPFD stays above minimum i spoke of above. A cheap lux meter can guage releative intensity -- you don't want a huge % drop-off from center to the sides, if you can avoid it. Closer is better than furhter away. Although there is not loss or gain of energy and mass, it can be absorbed and otherwise miss the plant. You want to limit how much bounces off the walls while still providing an even blanket of intensity -- as best you can. Simple as that,eh?