Deduction u/s 54 on sale of multiple residential houses

Earlier the exemption u/s. 54 was available for each house property purchased against each house property sold. But after recent amendment investment is restricted to 'a house property in India".. Literally its interpreted that any investment in second house property will be disallowed, but there should not be any restriction when the LTCG of both HP is invested in a single HP to claim exemption u/s. 54. No case law over the issue after the recent amendment.

As amemded by Finance Act 2019-

LTCG on sale of residential house property will be exempt if Capital gains is invested in two residential house
properties in India (“new houses”) .

The amount of capital gain exempt here is limited to Rs 2 crore.
The benefit is available only once in a life time of the tax payer.

Since you have invested in one property only, in my opinion exemption shall be allowed.

Hope it helps.