Official forgot to stamp my passport

[lear]

Hello,
Upon 1,5 months after arrival, I noticed that the official did not stamp my passport, while my parent's (who was traveling with me, passport was stamped. I hold global talent visa, and I was away for almost 2 months when I returned. So, it could be a problem for me in future when applying for ILR, if I have more travels this year and if the exceed 6 months. Where do I start? Who should I contact with this? I applied for a visa to Japan from Lonon during the last month. I can use it as a proof of being in counrty...I also have a stamp when departing to London from the origin country (but not on arrival).

[lolo2]

Upon 1,5 months after arrival, I noticed that the official did not stamp my passport,... So, it could be a problem for me in future when applying for ILR?

No, that's not an issue at all.