I know it's been years since anyone looked at my meters as my electrician cut the seals on the master fuse 10 years ago and no one has been near it to even notice the seals aren't there.
I will add, the meter is in a room I'm using for storage and it's a 5 minute job for me to get a meter reading. They aren't going to be sending anyone in that room for a while.
Your "Electrician" should have put a temporary seal on and notified the D.N.O If he removed the seal to " isolate the supply in an emergency" (the only reason NON DNO authorised personal are allowed to break the seal)
It's a common problem ,people pull the DNO's head/ main fuse to make dead to fit new consumer units.
technically even real ,qualified ,certified electricians are NOT allowed to remove DNO seals
if the seal is missing when the electricity supplier does a safety inspection (every 5 years on Gas or electric IIRC ) then you could be fined and billed £££££ for meter tampering
I advise you get your "electrician" to purchase and fit
seals clicky