One of 2 things are going on. Either:
1) Ink is not flowing correctly (issue is with the cartridges), or
2) The printheads are clogged (in the printer)
Both issues can be resolved.
First, lets rule out #1 above (that ink is not flowing properly):
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For ink cartridges to print as they are expected to print, there needs to be no impediment to the flow of ink in the cartridges.
1) In order to ensure that ink can flow adequately through ink cartridges, make sure that there is no adhesive tape covering the air passage near the top of the cartridges (the air passage would have been covered by a yellow tape that says "pull"). Pulling that tab is supposed to expose a tiny air passage. Sometimes the plastic tab seal leaves some glue behind, so please ensure that the area is free of any glue or tape so that the cartridge can "breathe" through the air hole. Also, ensure that the "breather plug" is removed from the cartridge, this is located here:
https://unikit.desk.com/customer/portal/articles/1123894-inkedibles-cartridges---breather-holes-need-to-be-exposed-before-printing?b_id=1362
2) Take the cartridges out of the printer and try squeezing some ink out by putting a little pressure on the sides. Below you will find instructions on how this can be done. Please remember to do this over a paper towel or several paper towels.
- With the nozzle port facing down toward the paper towel, place your fingers on each side of the cartridge.
- Be sure to place your fingers on the sponge chamber side and not the ink chamber side.
- Gently squeeze until a drop or two pushes out the nozzle port.
- Repeat the last step 1 more time.
If ink comes out of the cartridges after following this step, that means that ink is flowing adequately through the cartridge and the issue is in the printer.
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If ink comes out of the cartridges per above steps, then we know that the issue is not with ink flow, but rather with a printhead clog. To troubleshoot this:
1) Place the cartridges in your printer, and on a plain sheet of paper, print a nozzle test page.
Please write back with the results of the nozzle test so we can advise from there. Typically, if the nozzle test shows 1 or more cartridge nozzles clogged, the printer will give you the option to run a printhead cleaning cycle which usually will resolve the issue. If the clog is too much for the printer to resolve on its own, you may need cleaning cartridges, or a cleaning flush system. This article explains printhead clogs and options to resolve clogs in more details:
https://unikit.desk.com/customer/portal/articles/1053407-edible-ink-can-it-clog-what-can-i-do-to-minimize-the-risk-of-clogging-how-do-i-know-if-it-clogs-what-can-i-do-if-it-clogs-?b_id=1362