The service process of sessions in 3GPP New Radio (NR) wireless access systems operating in millimeter wave frequency band is heavily affected by the dynamic blockage of propagation paths between user equipment (UE) and access point (AP). Although the ability of UEs' transievers to operate over reflected propagation path components partially compensates for this phenomenon, it simultaneously leads to the dynamic fluctuations in the amount of resources requested during the session lifetime to support the required bitrate. In our study, we formulate an accurate model of the 3GPP NR AP service process by taking into account time-varying changes in the amount of requested resources caused by dynamic blockage of propagation paths. The derived metrics of interest includes new and ongoing session drop probabilities as well as the system resource utilization. The presented numerical results indicate that the presence of blockage events decreases the probability of session drops upon arrival at the expense of increasing blocking probability during the service process. However, it does not drastically affect the system resource utilization. Copyright © 2018 for the individual papers by the papers' authors.