The pool and spa cannot be heated at the same time.
The pool will be pre-heated to 84°F, except during the summer season. The spa is pre-set to 102°F, however it will not be pre-heated to 102°F, it will be pre-heated to 84°F. As mentioned the pool heater will only heat the pool and spa together (if waterfall feature is enabled) or the spa.
Please check and make sure the pool is at 84°F and then switch the heater to spa mode and make sure it is heating up to 102°F upon check-in.