A quick Google search does show some other P9 users experiencing calling issues with the Nougat update but no obvious solutions.
Since the Huawei P9 (EVA-L19) was not available through a Canadian carrier, you'll want to check with Huawei support directly. Huawei Canada doesn't have that phone listed in their support section so you could try asking them but they may not be able to help. You might need to find the country of origin that phone was imported from and try Huawei support there.
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