Hello. Your question is missing data, which makes it difficult to answer it with exactness, but I will try to help you in the best possible way.
If the reaction absorbs energy it means that the reaction is endothermic. This is because endortemic reactions are those that absorb energy from the environment, as opposed to exothermic reactions that release energy into the environment.
In that case, if the reaction is absorbing energy, it is appropriate for the water bath temperature to drop.