Since walking 2 miles per day and tracking heart rate
60-80 is the ideal rate
I understand your concerns. Exercise should have resulted in lower resting heart rates, not higher ones! Since this is an unexpected outcome, you should make sure it's correct. An arrhythmia - for example - may 'confuse' a device. Palpation or auscultation or - even better - an electrocardiogram are the most appropriate methods to determine the heart rate.
If your resting heart rate is indeed higher than 90 beats per minute then this is too high. Checking the thyroid status with a TSH, checking for anemia (low hematocrit) or other disorders would be indicated. The ideal resting heart rate lies between 60 and 80 beats per minute.
So in conclusion the best way to deal with this annoyance would be to do an electrocardiogram to determine the resting heart rate objectively and also detect potential arrhythmias. If the heart rate is high then investigating the cause should be your next step.
I hope I've answered your question. Please let me know if you need further assistance.