Asking for advice on handling TPM

I work as a PM. In my team there are a few PMs. I look after one work stream and in this workstream there is also a EM with his team. We have a TPM. I am meant to work closely with the EM to set priorities etc etc. lately I have found the TPM wants to be involved in everything. I was meant to work with the EM to create a roadmap and the TPM arranged the meeting and took the lead. There has been several times this has happened. I feel the TPM takes in my role when not needed and feel if I am working in something they want to do the work. How do we set boundaries between TPM work and my PM work. I have tried to be vague as avoiding doxxing myself a little