Ya not an issue, the seed shell can sometimes hang there even while the cotyledons are trying to develop after punching up through soil or medium.
I'd watch a plant with shell on it after it has sprouted above ground and is trying to unfurl its cotyledons. If after two days above ground and trying to unfurl cotyledons it still hasn't shed the shell I'd gently over the next two days try to ease the shell off the plant. Give it a little help over the course of 2-3 days and give plant a little help to shed and give chance to absorb light on newly sprouted cotyledons.
Lot of stuff happens over course of life to plants just like ppl. A lot of negative symptoms seem to be able to be corrected with adjustments to nutrition(water, nutes, medium) and environment. So give it a couple of days after seeing an issue and evaluate and adjust your controls b/c thats the only way you are going to be able to learn and become better grower.
GL