Converting Team (Classic site) to Communication site using Powershell

[sharepointadmin2912]

We would really appreciate your help on this matter. We have a classic team site on the root site, using powershell, it mentioned that we have to convert it into communication site, we followed various articles and it did create a page in the root site as a communication site.

The challenge is when we try to apply the source template in XML, it says access denied, and we are not able to proceed.

Appreciate your help on this matter.