It is best practice to use two sticks that come from the same kit, even if that means that you buy two identical single sticks. While they might and probably will work just fine, there is less of a chance for instability with a single kit of 2 x whatever size.
Have you tested each of your 2x32gb sticks individually to see if the system will boot? There might be a bad socket, problem with the memory controller, or something wrong with one of the sticks.
If the sticks are currently installed like this: stick 1 & stick 2 in slot 1 & slot 2
Try different combinations to look for a boot:
- Only stick 1 in slot 1
- Only stick 2 in slot 1
- Only stick 2 in slot 2
- Only stick 1 in slot 2
If both scenarios 1 & 2 work, then you know the slot for slot 1 is fine. The same logic works for 3 & 4 with slot 2. If 1 & 4 or 2 & 3 end up not working, then you can narrow down that it is a problem with one of the sticks.